JP5305242B2 - Pixel drive circuit, light emitting device, drive control method thereof, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pixel driving circuit, a light emitting device and a drive control method for the same, capable of causing a light emitting element to perform light emitting operation in a suitable luminance gradation according to image data. <P>SOLUTION: A pixel PIX includes the pixel driving circuit DC, and an organic EL element OEL. The pixel driving circuit DC includes: a transistor Tr13 connected in series to an anode of the organic EL element OEL; a transistor Tr11 for putting the transistor Tr13 in diode connection state in writing the image data; a transistor Tr12 for writing voltage component according to the image data to a capacitor Cs connected between gate/source terminals of the transistor Tr13 in the writing operation state; and a capacitor Cc connected between the transistor Tr12 and the source terminal of the transistor Tr13. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a pixel drive circuit, a light-emitting device, a drive control method thereof, and an electronic device, and more particularly, a current-driven light-emitting element and a pixel that emit light at a predetermined luminance gradation by supplying a current according to image data. The present invention relates to a light emitting device including a light emitting panel in which a plurality of pixels each having a drive circuit are arranged, a driving control method thereof, and an electronic apparatus to which the light emitting device is applied.

  In recent years, current-driven (or current-controlled) light-emitting elements such as organic electroluminescence elements (organic EL elements) and light-emitting diodes (LEDs) are used in the form of a matrix as next-generation display devices following liquid crystal display devices. A light-emitting element type display device (light-emitting element type display, light-emitting device) including a display panel arranged in a vertical direction has attracted attention.

  In particular, a light-emitting element display using an active matrix driving method has excellent display characteristics such as a higher display response speed and a smaller viewing angle dependency than a liquid crystal display device. In addition, unlike the liquid crystal display device, there is a feature in the device configuration that a backlight and a light guide plate are not required. Therefore, application to various electronic devices is expected in the future.

  For example, an organic EL display device described in Patent Document 1 is an active matrix drive display device in which current is controlled by a voltage signal, and a voltage signal corresponding to image data is applied to a gate to supply current to the organic EL element. A current control thin film transistor to be supplied and a switching thin film transistor that performs switching for supplying a voltage signal corresponding to image data to the gate of the current control thin film transistor are provided for each pixel.

JP-A-8-330600

  In an organic EL display device using a voltage-designated gradation control method that controls gradation using such a voltage signal, the element characteristics (such as on-resistance) of the thin film transistor and the element characteristics (resistance of the organic EL element) Etc.) and the change in characteristics caused by the usage environment, etc. affect the writing of voltage signals according to the image data and the current value of the current supplied to the organic EL element. For this reason, it is difficult to cause the organic EL element to stably perform a light emission operation at an appropriate luminance gradation according to the image data, and there is a problem that the image quality is deteriorated such as luminance unevenness.

  Accordingly, in view of the above-described problems, the present invention provides a pixel driving circuit, a light emitting device, a driving control method thereof, and an electronic apparatus capable of causing a light emitting element to emit light with an appropriate luminance gradation according to image data. For the purpose.

The invention according to claim 1 is a pixel driving circuit that has a light emitting element and operates the light emitting element in a pixel connected to a data line, the first capacitor element, and the first capacitor element One end and the other end are connected to one end of the current path and a control terminal, a drive control element for supplying the light emitting element with a drive current flowing in the current path in accordance with the charge accumulated in the first capacitor element, and one end And a second capacitive element connected to one end of the first capacitive element, and the first capacitive element has an image of a potential at the other end of the second capacitive element via the data line. After the first potential corresponding to the data is set , the charge corresponding to the image data is accumulated by setting the second potential different from the first potential, and the pixel driving circuit further includes: One end of the second capacitor and the second power When the other end of the second capacitive element is set to the first potential, the one end of the second capacitive element is connected to the electrode. characterized Rukoto which have a reset control device.

According to a second aspect of the present invention, in the pixel driving circuit according to the first aspect, the pixel driving circuit includes a first selection control element that controls conduction between the other end of the current path of the drive control element and a control terminal, The first selection control element is controlled to connect the other end of the current path of the drive control element and a control terminal when charge is accumulated in the first capacitor element and the second capacitor element. It is characterized by that.
According to a third aspect of the invention, the pixel driving circuit according to claim 1 or 2, wherein the reset control element, said second potential said other end from said first potential of said second capacitor In this case, the connection between the one end of the second capacitor and the electrode is controlled.
The invention according to claim 4, in the pixel driving circuit according to any one of claims 1 to 3, the second selection control for controlling the conduction between the other end of the data line and the second capacitor has a device, the second selection control element, the other end of the in the other end of the second capacitor is set to the first potential, said data lines and said second capacitor And is controlled to be connected to each other.

The invention of claim 5 is a light-emitting device driven in accordance with the image data, driving a plurality of pixels, a light emitting panel having a plurality of data lines connected to the each pixel, the light emitting panel Each pixel includes a light emitting element, a first capacitor element, one end and the other end of the first capacitor element connected to one end of a current path and a control terminal. A drive control element for supplying the light emitting element with a drive current flowing in the current path in accordance with the electric charge accumulated in the capacitive element; a second capacitive element having one end connected to one end of the first capacitive element; and wherein the first capacitive element, after the potential of the other end of the second capacitive element via the data line is set to a first potential corresponding to the image data, the first It said image by being set to a second potential different from the potentials Charge corresponding to chromatography data is stored, each pixel is further configured to control conduction between the electrodes is set at one end and the second potential of the second capacitor, said second capacitor A reset control element that connects one end of the second capacitor and the electrode when the other end is set to the first potential; and the drive circuit includes the image data on the data line. a voltage corresponding to applied, and having a data driving circuit for setting said second potential to the potential of the other end after setting the first potential of the second capacitor.

According to a sixth aspect of the present invention, in the light emitting device according to the fifth aspect , the data driving circuit includes a voltage generating circuit for generating a voltage according to the image data, and the data line is connected to the voltage generating circuit. Or a connection switching circuit for switching connection to the contact point set to the second potential.
According to a seventh aspect of the present invention, in the light emitting device according to the fifth or sixth aspect , each pixel has a first selection control that controls conduction between the other end of the current path of the drive control element and a control terminal. and the element, and a second selection control element for controlling the conduction between the other end of the data line and the second capacitive element, wherein the driving circuit, the first selection control element and the second and controls the second selection control element, when for accumulating charges in the first capacitor and the second capacitor, connects the other end to the control terminal of the current path of the drive control device, wherein characterized in that it has a selection drive circuit for connecting the other end of the data line and the second capacitor.
Invention according to claim 8, in the light-emitting device according to claim 7, wherein the selection drive circuit, the controls the reset control element, the other end of said first potential of said second capacitor when set to, and connecting said one end of said second capacitor electrode, when the end of the second capacitive element is set to the second potential from said first potential The connection between the one end of the second capacitor element and the electrode is released.
An electronic apparatus according to a ninth aspect of the invention is characterized in that the light emitting device according to any one of the fifth to eighth aspects is mounted.

The invention according to claim 10 is a drive control method of a light emitting device driven according to image data, wherein the light emitting device includes a light emitting element, a first capacitor element, and a first capacitor element. One end and the other end are connected to one end of the current path and a control terminal, a drive control element for supplying the light emitting element with a drive current flowing in the current path in accordance with the charge accumulated in the first capacitor element, and one end And a second capacitive element connected to one end of the first capacitive element, and a light emitting panel having a plurality of pixels, and the other end of the second capacitive element of each pixel is connected to the image data. a first write operation step of setting a first potential corresponding to the second end of the second capacitor of each pixel after setting the first potential, the second capacitive element the other end is set to a second potential different from the first potential, A second write operation step of accumulating the charge corresponding to the image data to the serial first capacitor, is executed prior to the first write operation step, one end and the second of said second capacitor And a reset operation step of connecting an electrode set at a potential of λ .

According to an eleventh aspect of the present invention, in the drive control method for a light emitting device according to the tenth aspect , the first writing step and the second writing operation step include the data line and the second capacitor element. A first connection operation step for connecting the other end; and a second connection operation step for connecting the other end of the current path of the drive control element and a control terminal.
A twelfth aspect of the present invention is the light emitting device drive control method according to the tenth or eleventh aspect , wherein the second writing operation step releases the connection between one end of the second capacitive element and the electrode. And a release operation step.

  According to the pixel drive circuit, the light-emitting device, and the drive control method thereof according to the present invention, an electronic device that can cause a light-emitting element to emit light at an appropriate luminance gradation according to image data and has a good and uniform image quality. Can be realized.

1 is a schematic configuration diagram showing a first embodiment of a display device according to the present invention. It is a schematic block diagram which shows an example of the data driver applicable to the display apparatus which concerns on 1st Embodiment. FIG. 2 is a schematic circuit configuration diagram illustrating an example of a data driver applicable to the display device according to the first embodiment. It is a circuit block diagram which shows one Embodiment of the pixel (pixel drive circuit and light emitting element) applied to the display panel which concerns on 1st Embodiment. 3 is a timing chart illustrating a display operation in the display device according to the first embodiment. It is an operation | movement conceptual diagram which shows the reset operation | movement in the display apparatus which concerns on 1st Embodiment. It is an operation | movement conceptual diagram which shows the 1st write-in operation | movement in the display apparatus which concerns on 1st Embodiment. It is an operation | movement conceptual diagram which shows the 2nd write-in operation | movement in the display apparatus which concerns on 1st Embodiment. It is an operation | movement conceptual diagram which shows the light emission operation | movement in the display apparatus which concerns on 1st Embodiment. 6 is a timing chart when the display operation according to the first embodiment is applied to a display panel in which pixels are two-dimensionally arranged. It is a circuit block diagram which shows an example of the pixel as a comparison for demonstrating the predominance of the effect of the pixel drive circuit which concerns on 1st Embodiment, a display apparatus, and its drive control method. It is a perspective view which shows the structure of the digital camera concerning 2nd Embodiment. It is a perspective view which shows the structure of the mobile type personal computer concerning 2nd Embodiment. It is a figure which shows the structure of the mobile telephone concerning 2nd Embodiment.

  Hereinafter, a pixel drive circuit, a light emitting device, and a drive control method thereof according to the present invention will be described in detail with reference to embodiments. In the present embodiment, the light emitting device is described as a display device.

<First Embodiment>
(Display device)
First, a schematic configuration of a display device according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing a first embodiment of a display device according to the present invention.

  As shown in FIG. 1, a display device (light emitting device) 100 according to the present embodiment is schematically shown as a display panel (light emitting panel) 110, a selection driver (selection drive circuit) 120, and a power supply driver (power supply drive circuit) 130. And a data driver (data driving circuit) 140, a system controller 150, and an image signal generation circuit 160. Here, the configuration including at least the selection driver 120, the power supply driver 130, and the data driver 140 corresponds to the drive circuit in the present invention.

  As shown in FIG. 1, the display panel 110 has a plurality of two-dimensional arrays (for example, n rows × m columns; n and m are positive integers) in a row direction (left and right direction in the drawing) and a column direction (up and down direction in the drawing). A plurality of first selection lines Ls1 and second selection lines Ls2 arranged to be connected to the pixels PIX arranged in the row direction, and connected to all the pixels PIX in common. Power source line La and a plurality of data lines Ld arranged to be connected to the pixels PIX arranged in the column direction. Here, each pixel PIX includes a pixel drive circuit and a light emitting element (display element), as will be described later.

  The selection driver 120 is connected to each of the first and second selection lines Ls1 and Ls2 disposed on the display panel 110, and is based on a selection control signal supplied from a system controller 150 to be described later. The first and second selection signals Vsel1, Vsel2 having a predetermined voltage level (selection level, non-selection level) are sequentially applied to the second selection lines Ls1, Ls2 at a predetermined timing.

  Although not shown, the selection driver 120 is a shift register that sequentially outputs shift signals corresponding to the first and second selection lines Ls1 and Ls2 of each row based on a selection control signal supplied from the system controller 150. Then, the shift signal is converted to a predetermined signal level (selection level) and sequentially output as the first and second selection signals Vsel1 and Vsel2 to the first and second selection lines Ls1 and Ls2 of each row (output) A buffer) can be applied.

  The power supply driver 130 is connected to a power supply line La commonly connected to each pixel PIX of the display panel 110, and is supplied to the power supply line La at a predetermined timing based on a power supply control signal supplied from a system controller 150 described later. A power supply voltage Vsa having a voltage level (display level, non-display level) is applied.

  The data driver 140 is connected to each data line Ld of the display panel 110, and based on a data control signal supplied from a system controller 150, which will be described later, at least during a display operation, a gradation signal (gradation voltage) corresponding to image data. Vdata) is generated and supplied to the pixel PIX via each data line Ld.

  FIG. 2 is a schematic block diagram illustrating an example of a data driver applicable to the display device according to the present embodiment. FIG. 3 is a schematic circuit configuration diagram showing an example of an output circuit of the data driver shown in FIG. Here, in FIG. 3, only the D / A converter 144 and the output circuit 145 are shown, and the illustration of the data driver 140 is simplified.

  For example, as shown in FIG. 2, the data driver 140 includes a shift register circuit 141, a data register circuit 142, a data latch circuit 143, a D / A converter 144, and an output circuit 145.

  The shift register circuit 141 sequentially outputs shift signals based on data control signals (shift clock signal CLK, sampling start signal STR) supplied from the system controller 150. The data register circuit 142 sequentially captures the image data D0 to Dm for one row supplied from the image signal generation circuit 160 based on the input timing of the shift signal. The data latch circuit 143 holds the image data D0 to Dm for one row taken into the data register circuit 142 based on the data control signal (data latch signal STB). A D / A converter (voltage generation circuit) 144 converts the held image data D0 to Dm into a predetermined analog signal voltage based on gradation reference voltages V0 to VP supplied from power supply means (not shown). Convert to Vpix. The output circuit (voltage generation circuit) 145 converts the image data converted into the analog signal voltage into a gradation voltage Vdata of a predetermined signal level (positive voltage), and a data control signal (output) supplied from the system controller 150 Based on the switching / enable signal OE), the data lines Ld are simultaneously output to the data lines Ld of the columns corresponding to the image data.

  In particular, in the data driver 140 applied to the present embodiment, as shown in FIG. 3, the output circuit 145 includes a changeover switch (connection changeover circuit) 145a connected to the data line Ld of each column, and a D / A And a follower amplifier 145b for driving the output of the converter 144.

  The changeover switch 145a selectively connects the data line Ld to one of the contacts Na and Nb based on the data control signal supplied from the system controller 150. The contact point Na is connected to the D / A converter 144 via the follower amplifier 145b, and the analog signal voltage Vpix corresponding to the image data output from the D / A converter 144 is converted to a predetermined signal level, so that the gradation voltage Vdata As applied. The contact Nb is set to the ground potential GND.

  In the present embodiment, the changeover switch 145a is connected to the contact Nb at the first writing timing, as described later, when writing image data to the pixels PIX arranged in the display panel 110, and then, It is set to be connected to the contact Na at the second write timing and to be connected to the contact Nb at the subsequent third write timing. As a result, the ground potential GND is applied to the data line Ld at the first writing timing during the image data writing period, and the gradation voltage Vdata corresponding to the image data is applied to the data line Ld at the second writing timing. The ground potential GND is applied to the data line Ld at the third write timing.

  The system controller 150 controls the operation states of the selection driver 120, the power supply driver 130, and the data driver 140 based on a timing signal supplied from an image signal generation circuit 160 described later, and performs predetermined drive control in the display panel 110. A selection control signal, a power supply control signal, and a data control signal for executing the operation are generated and output.

  In particular, in the present embodiment, the system controller 150 operates the selection driver 120, the power supply driver 130, and the data driver 140 at a predetermined timing, and performs the first and second selection signals Vsel1, Vsel2 and the power supply at predetermined voltage levels. The voltage Vsa and the gradation voltage Vdata corresponding to the image data are generated and output. As a result, the system controller 150 performs a control to display each pixel PIX with a display operation (light emission operation) and display predetermined image information based on the video signal on the display panel 110.

  For example, the image signal generation circuit 160 generates image data (luminance gradation data) based on a video signal supplied from the outside of the display device 100 and supplies the image data to the data driver 140, and based on the image data. A timing signal (system clock or the like) for displaying predetermined image information on the display panel 110 is extracted or generated and supplied to the system controller 150.

  More specifically, the image signal generation circuit 160 extracts a luminance gradation signal component from the video signal, and for each row of the display panel 110, the luminance gradation signal component is converted into image data (luminance) including a digital signal. Is supplied to the data register circuit 142 of the data driver 140 as gradation data. Here, when the video signal includes a timing signal component that defines the display timing of image information, such as a television broadcast signal (composite video signal), the image signal generation circuit 160 includes the luminance gradation signal component. In addition to the function of extracting the timing signal component, the timing signal component may be extracted and supplied to the system controller 150. In this case, the system controller 150 generates control signals to be individually supplied to the selection driver 120, the power supply driver 130, and the data driver 140 based on the timing signal supplied from the image signal generation circuit 160. .

(Pixel)
Next, the pixels arranged in the display panel according to the present embodiment will be specifically described.
FIG. 4 is a circuit configuration diagram showing one embodiment of a pixel (pixel drive circuit and light emitting element) applied to the display panel according to this embodiment.

  As shown in FIG. 4, the pixels PIX arranged in the display panel 110 according to the present embodiment have a configuration including a pixel driving circuit DC and an organic EL element (current-driven light emitting element) OEL. ing. The pixel drive circuit DC discharges the charge written in the pixel PIX based on at least the first selection signal Vsel1 applied from the selection driver 120 via the first selection line Ls1, and sets the second selection line Ls. The pixel PIX is set to a selected state based on the selection signal Vsel2 applied through the data driver 140, and a light emission driving current corresponding to the gradation voltage Vdata supplied from the data driver 140 through the data line Ld is generated. The organic EL element OEL emits light with a predetermined luminance gradation based on the light emission drive current generated in the pixel drive circuit DC.

  Specifically, the pixel drive circuit DC shown in FIG. 4 includes transistors Tr11 to Tr14 and capacitors Cs and Cs. The transistor (diode connection transistor; first selection control element) Tr11 has a gate terminal connected to the second selection line Ls2, a drain terminal connected to the power supply line La, and a source terminal connected to the contact N11. Has been. The transistor (selection transistor; second selection control element) Tr12 has a gate terminal connected to the second selection line Ls2, a source terminal connected to the data line Ld, and a drain terminal connected to the capacitor Cc. Yes. The transistor (drive transistor; drive control element) Tr13 has a gate terminal connected to the contact N11, a drain terminal connected to the power supply line La, and a source terminal connected to the contact N12. The transistor (reset transistor; reset control element) Tr14 has a gate terminal connected to the first selection line Ls1, a drain terminal connected to the contact N12, and a source terminal connected to a common electrode provided in common to all the pixels PIX. A common voltage Vcom set to a constant low voltage (for example, ground potential GND) is applied. Further, the capacitor (auxiliary capacitor; first capacitor element) Cs is connected between the gate terminal (contact N11) and the source terminal (contact N12) of the transistor Tr13. Further, the capacitor (coupling capacitance; second capacitance element) Cc is connected between the drain terminal of the transistor Tr12 and the contact N12.

  The organic EL element OEL has an anode connected to the contact N12 of the pixel drive circuit DC and a cathode connected to the common electrode, and is applied with the common voltage Vcom.

  Here, in the pixel PIX shown in FIG. 4, the transistors Tr11 to Tr14 are not particularly limited. For example, well-known thin film transistors (TFTs) having the same channel type can be applied. The transistors Tr11 to Tr14 may be amorphous silicon thin film transistors or polysilicon thin film transistors. That is, in the transistors Tr11 to Tr14 described above, the gate terminal corresponds to the control terminal in the present invention, and the source and drain terminals correspond to one end side or the other end side of the current path in the present invention.

  In particular, when the transistors Tr11 to Tr14 are composed of n-channel amorphous silicon thin film transistors, a simple manufacturing process is applied compared to polycrystalline or single crystal thin film transistors by applying an already established amorphous silicon manufacturing technique. Thus, a transistor with uniform and stable operating characteristics (such as electron mobility) can be realized. The capacitor Cs may be a parasitic capacitance formed between the gate and drain of the transistor Tr14, or may be a capacitor in which separate capacitance elements are connected in parallel in addition to the parasitic capacitance.

  Further, in the pixel PIX described above, the circuit configuration including the three transistors Tr11 to Tr14 as the pixel driving circuit DC is shown, but the present invention is not limited to this embodiment, and four or more transistors are provided. It may have other circuit composition provided with. Further, the circuit configuration in which the organic EL element OEL is applied as a light emitting element driven to emit light by the pixel driving circuit DC is shown, but the present invention is not limited to this, and any current driven light emitting element can be used. For example, another light emitting element such as a light emitting diode may be used.

(Display device drive control method)
Next, a drive control method (display operation) in the display device according to the present embodiment will be described.
FIG. 5 is a timing chart showing a display operation in the display device according to the present embodiment. FIG. 6 is an operation concept diagram showing a reset operation in the display operation of the display device according to the present embodiment. FIG. 7 is an operation concept diagram showing a first writing operation in the display device according to the embodiment. FIG. 8 is an operation conceptual diagram showing a second writing operation in the display device according to the present embodiment, and FIG. 9 is an operation conceptual diagram showing a light emitting operation in the display device according to the present embodiment. 6 to 9, the configuration of the data driver 140 is simplified by showing only the D / A converter 144 and the output circuit 145.

  In the display operation according to the present embodiment, as shown in FIG. 5A, the charge written in the pixel PIX is discharged and the pixel PIX is reset during a predetermined display period (one processing cycle period) Tcyc. The reset period Trst, the first writing period Twa in which the gradation voltage Vdata corresponding to the image data is applied to the data line Ld to write the gradation voltage Vdata in the pixel PIX, and the ground potential GND is applied to the data line Ld. The writing period Twrt having the second writing period Twb for writing the voltage (−Vdata) corresponding to the gradation voltage Vdata to the pixel PIX, and light emission for causing the light emitting element to emit light at a predetermined luminance gradation corresponding to the image data. Period Tem (Tcyc ≧ Trst + Twa + Twb + Tem).

  First, in the reset period Trst, as shown in FIGS. 5A and 6A, a low level (ground potential GND) power supply voltage Vsa is applied to the power supply line La connected to the pixel PIX. A high level (selection level) selection signal Vsel1 is applied to the first selection line Ls1, and a high level (selection level) selection signal Vsel2 is applied to the second selection line Ls2. In synchronism with this timing, as shown in FIGS. 5A and 6A, the changeover switch 145a provided in the output circuit 145 of the data driver 140 is switched and connected to the contact Nb. The line Ld is set to the ground potential GND. FIG. 6B shows an equivalent circuit at this time.

  As a result, as shown in FIG. 6A, the transistor Tr11 provided in the pixel drive circuit DC of the pixel PIX is turned on, and the gate terminal (contact N11) of the transistor Tr13 and one end side of the capacitor Cs (transistor Tr13). Is set to the ground potential GND. Further, the transistor Tr12 is turned on, and the other end side (the drain terminal side of the transistor Tr12) of the capacitor Cc is set to the ground potential GND. Further, the transistor Tr14 is turned on, and the source terminal (contact N12) of the transistor Tr13 and one end side (contact N12 side) of the capacitor Cc are set to the ground potential GND.

  Therefore, both ends of the capacitors Cs and Cc are set to the same potential, and the charges accumulated in the capacitors Cs and Cc are discharged. At this time, in the transistor Tr13, the transistor Tr11 is turned on and the drain terminal and the gate terminal are connected. However, since the drain terminal and the source terminal of the transistor Tr13 are both set to the ground potential GND, the transistor Tr13 is turned off. It has become. At this time, since the transistor Tr13 substantially acts as a high resistance, the transistor Tr13 is shown as a resistance Rtr in the equivalent circuit shown in FIG. The organic EL element OEL does not emit light because the anode and cathode are set to the same potential and no current flows.

  Next, in the first writing period Twa, as shown in FIGS. 5A and 7A, the low-level (ground potential GND) power supply voltage Vsa is applied to the power supply line La connected to the pixel PIX. In the applied state, a low level (non-selection level) selection signal Vsel1 is applied to the first selection line Ls1, and a high level (selection level) selection signal Vsel2 is applied to the second selection line Ls2. In synchronism with this timing, as shown in FIGS. 5A and 7A, the changeover switch 145a provided in the output circuit 145 of the data driver 140 is connected to the contact Na to switch the data. A gradation voltage Vdata corresponding to the image data is applied to the line Ld. FIG. 7B shows an equivalent circuit at this time.

  As a result, as shown in FIG. 7A, the transistor Tr11 provided in the pixel drive circuit DC of the pixel PIX is turned on, and the ground potential GND is applied to the gate terminal (contact N11) of the transistor Tr13. Further, the transistor Tr12 is turned on, and the gradation voltage Vdata is applied to the other end side (the drain terminal side of the transistor Tr12) of the capacitor Cc. At this time, the transistor Tr14 is turned off, and the ground potential GND set in the reset period Trst is set via the organic EL element OEL in which the source terminal (contact N12) of the transistor Tr13 functions substantially as a high resistance. Is held in. In the transistor Tr13, the transistor Tr11 is turned on and the drain terminal and the gate terminal are connected. However, since the drain terminal and the source terminal of the transistor Tr13 are both set to the ground potential GND, the transistor Tr13 is in the off state. . Accordingly, charges corresponding to the gradation voltage Vdata are accumulated in the capacitor Cc connected between the transistor Tr12 and the contact N12. The organic EL element OEL does not emit light because the anode and cathode are at the same potential and no current flows.

  FIG. 5A shows a drive control method in which the transistor Tr14 is turned off by applying a low level (non-selection level) selection signal Vsel1 to the first selection line Ls1 in the first writing period Twa. The source terminal (contact N12) of the transistor Tr13 is set in a floating state. However, as shown in FIG. 5B, the high level (selection level) is applied to the first selection line Ls1 even in the first writing period Twa. The selection signal Vsel1 may be applied to turn on the transistor Tr14. In this case, the source terminal (contact N12) of the transistor Tr13 can be forcibly set to the ground potential GND during the first writing period Twa. Thereby, it is possible to more stably accumulate charges according to the gradation voltage Vdata in the capacitor Cc.

  Next, in the second write period Twb, as shown in FIGS. 5 and 8A, the low-level (ground potential GND) power supply voltage Vsa is applied to the power supply line La, and the first select line Ls1 is low. With the level (non-selection level) selection signal Vsel1 being applied and the high level (selection level) selection signal Vsel being applied to the second selection line Ls2, the selector switch 145a of the data driver 140 is switched and connected to the contact Nb. As a result, the data line Ld is set to the ground potential GND.

As a result, as shown in FIG. 8A, the gate terminal (contact N11) of the transistor Tr13 of the pixel drive circuit DC is set to the ground potential GND, and the other end side of the capacitor Cc (the drain terminal side of the transistor Tr12). ) Is set to the ground potential GND. At this time, the transistor Tr14 is turned off and the source terminal (contact N12) of the transistor Tr13 is in a floating state, but the potential on the other end side of the capacitor Cc changes from the gradation voltage Vdata to the ground potential GND. As shown in FIG. 8B, the charge accumulated in the capacitor Cc is distributed to the capacitors Cc and Cs and the inter-terminal capacitance Cel of the organic EL element OEL, and the transistor Tr13 is turned on. Thus, the source terminal (contact N12) of the transistor Tr13, which is one end side of the capacitor Cc, is set to a potential represented by the following equation (1). Here, Vdata ′ is a write voltage, and ΔV is a voltage decrease amount. The magnitude of the voltage decrease amount ΔV will be described later.
−Vdata ′ = − (Vdata−ΔV) (1)

  Therefore, charges corresponding to the write voltage Vdata ′ are accumulated in the capacitor Cs connected between the gate and source of the transistor Tr13, and image data is written into the pixel PIX. As a result, the gate-source voltage Vgs of the transistor Tr13 is set to the write voltage Vdata ′ (Vgs = Vdata ′). At this time, the anode (contact N12) of the organic EL element OEL is set to a negative potential −Vdata ′, and the cathode is set to the ground potential GND. Therefore, a reverse bias is applied to the organic EL element OEL. Thus, no current flows through the organic EL element OEL, and no light emission operation is performed. Here, as will be described later, since the magnitude of the voltage decrease amount ΔV is a value that can be predicted in advance, the voltage value of the gradation voltage Vdata is set to the voltage decrease amount ΔV from the voltage value based on the gradation value of the image data. By correcting to a higher value, the voltage component charged in the capacitor Cs can be a voltage value based on the gradation value of the image data.

  Next, the voltage decrease amount ΔV will be described in detail. The voltage decrease amount ΔV is a total of a first factor that is caused by the charge accumulated in the capacitor Cc being distributed to the capacitors Cc, Cs, and Cel and a second factor that is caused when the transistor Tr13 is turned on. It becomes the amount.

First, the first factor will be described. As shown in FIG. 8B, in the first writing period Twa, after applying the gradation voltage Vdata to the data line Ld to accumulate charges in the capacitor Cc, the data line Ld is set to the ground potential GND ( Data line voltage; Vdata → GND), and the source terminal (contact point) of the transistor Tr13 when the transistor Tr13 is maintained in the OFF state at the time immediately after the start of the second writing period Twb (time t = 0). When the potential of N12) is Vn12 (0), this potential Vn12 (0) is because the contact N12 is in a floating state, and the charge accumulated in the capacitor Cc is distributed to the capacitors Cc, Cs, and Cel. It is expressed as the following formula (2).
Vn12 (0) = − Vdata × Cc / (Cc + Cs + Cel) (2)

Here, when Vn12 is expressed by the following equation (3) and ΔV1 is a voltage decrease amount due to the first factor, this voltage decrease amount ΔV1 is expressed by the following equation (4): Vn12 (0) = − (Vdata−ΔV1) (3)
ΔV1 = Vdata × (Cs + Cel) / (Cc + Cs + Cel) (4)

  In the equation (4), since the capacitors Cc, Cs, and Cel all have fixed capacitances (fixed values), the magnitude of the first voltage decrease amount ΔV1 due to the first factor can be predicted in advance. it can.

  Next, the second factor will be described. After the start of the second writing period Twb, the ground potential GND is applied to the drain terminal of the transistor Tr13, the potential of the source terminal (contact N12) changes to a negative potential (GND → −Vdata ′), and writing to the capacitor Cs is performed. When the voltage corresponding to the voltage Vdata ′ is charged, the write voltage Vdata ′ is applied between the gate and the source of the transistor Tr13, and the write voltage Vdata ′ is higher than the threshold voltage of the transistor Tr13. The transistor Tr13 is turned on. As a result, a current flows between the drain and the source of the transistor Tr13. Accordingly, the charge accumulated in the capacitor Cs immediately after the start of the second writing period Twb is turned on. It decreases with the passage of time through the drains.

  Here, when the potential of the contact N12 at the start of the second writing period Twb is Vn12 (0), the potential Vn12 (t of the contact N12 after the time t has elapsed from the start of the second writing period Twb. ) Is expressed by the following equation (5), and generally decreases from Vn12 (0) in inverse proportion to time t. Here, Vth is the threshold voltage of the transistor Tr13, β is the current amplification factor of the transistor Tr13, and C is the sum of the capacitance values of the capacitors Cc, Cs, and Cel.

  Here, when Vn12 (t) is expressed by the following equation (6) and ΔV2 is the second voltage decrease amount due to the second factor, the second voltage decrease amount ΔV2 is expressed by the following equation (7). And becomes a function of Vth, C, β, Vn12 (0) and time t.

In equation (7), Vth, C, β, Vn12 (0) and the value of time t corresponding to the time width of the second writing period Twb are known, so the second voltage decrease due to this second factor. The magnitude of the amount ΔV2 can also be predicted in advance.
The second voltage decrease amount ΔV2 due to the second factor is preferably small. The magnitude of the second voltage decrease amount ΔV2 depends on the time width of the second writing period Twb, and the time width is Since the second voltage decrease amount ΔV2 becomes larger as the length becomes longer, the time width of the second writing period Twb is set to the minimum time necessary for accumulating charges corresponding to the writing voltage Vdata ′ in the capacitor Cs. It is preferable to do.

  For example, when an amorphous silicon thin film transistor is applied to the transistor Tr13, the change in electrical characteristics of the transistor Tr13 with time is relatively large, and the value of the threshold voltage Vth may change with time. In the above equation (7), the magnitude of the second voltage decrease amount ΔV2 depends on the value of the threshold voltage Vth. However, the smaller the value of the time t in the equation (7), the smaller the influence of the change of the threshold voltage Vth on the value of the second voltage decrease amount ΔV2. Therefore, when the time width of the second writing period Twb is sufficiently shortened, the initial value, average value, or design value of the threshold voltage Vth of the transistor Tr13 may be used as the value of the threshold voltage Vth. .

  In the above equation (7), the magnitude of the second voltage decrease amount ΔV2 also depends on the value of the current amplification factor β. Even when an amorphous silicon thin film transistor is applied to the transistor Tr13, the current amplification factor β varies little over time, but there is variation in the value of the current amplification factor β of the transistor Tr13 of each pixel. However, also in this case, the smaller the value of time t in the equation (7), the smaller the influence of the variation in the value of the current amplification factor β on the value of the second voltage decrease amount ΔV2. Therefore, when the time width of the second writing period Twb is sufficiently shortened, the average value or the design value of the current amplification factor β of the transistor Tr13 of each pixel may be used as the value of the current amplification factor β.

  Next, in the light emission period Tem, as shown in FIGS. 5 and 9A, a low level (non-selection level) selection signal Vsel1 is applied to the first selection line Ls1, and a low level is applied to the second selection line Ls2. In a state where the selection signal Vsel2 of (non-selection level) is applied, the high-level power supply voltage Vsa is applied to the power supply line La. In synchronism with this timing, the data line Ld is set to the ground potential GND by switching the switch 145a of the data driver 140 to the contact Nb as shown in FIGS.

  As a result, as shown in FIGS. 9A and 9B, the transistors Tr11 and Tr12 provided in the pixel drive circuit DC of the pixel PIX are turned off, and the capacitor connected between the gate and source of the transistor Tr13. The charge accumulated in Cs is retained. A high level power supply voltage Vsa is applied to the drain terminal of the transistor Tr13. The voltage value of the power supply voltage Vsa is set such that the potential of the source terminal (contact N12) of the transistor Tr13 is applied with a forward bias to the organic EL element OEL.

  Therefore, the gate-source voltage Vgs of the transistor Tr13 is held by the write voltage Vdata ′ charged in the capacitor Cs, the transistor Tr13 is turned on and the drain current Ids flows, and the transistor Tr13 and the contact N12 are supplied from the power supply line La. The light emission drive current Iem flows in the direction of the power supply line Lc through the organic EL element OEL. Here, the light emission drive current Iem (drain current Ids) is written to the pixel PIX in the write operation, and the voltage of the write voltage Vdata ′ based on the gradation voltage Vdata held between the gate and the source of the transistor Tr13. Since it is defined based on the value, the organic EL element OEL emits light at a luminance gradation corresponding to the image data.

Next, the case where the display operation described above is executed on the display panel 110 in which the pixels PIX are two-dimensionally arranged will be described.
FIG. 10 is a timing chart when the display operation according to the present embodiment is applied to a display panel in which pixels are two-dimensionally arranged.

  In the display panel 110 shown in FIG. 1 in which the pixels PIX are two-dimensionally arranged, when a display operation is performed, as shown in FIG. 10, the reset period Trst and the first document for each row are included in the image data writing period Tdwt. A series of operations including the insertion period Twa and the second writing period Twb are sequentially performed on the pixels PIX in the first to nth rows of the display panel 110.

  First, in the reset period Trst of the first row of the image data writing period Tdwt, the high-level selection signal Vsel1 is applied to the first selection line Ls1 of the first row of the display panel 110 and the second selection line Ls2 is high. In a state where the level selection signal Vsel2 is applied and the power supply voltage Vsa of the low level (ground potential GND) is applied to the power supply line La, the data line Ld of each column is set to the ground potential GND. Thereby, both ends of the capacitors Cs and Cc are set to the same potential, and the charges accumulated in the capacitors Cs and Cc are discharged.

  Next, in the first writing period Twa of the first row, the low level selection signal Vsel1 is applied to the first selection line Ls1 of the first row of the display panel 110, and the high level selection signal Vsel2 is applied to the second selection line Ls2. , The low level selection signals Vsel1 and Vsel2 are applied to the first and second selection lines Ls1 and Ls2 of the second to nth rows, and the power supply voltage of the low level (ground potential GND) is applied to the power supply line La. In a state where Vsa is applied, a gradation voltage Vdata corresponding to image data is applied to the data line Ld of each column. As a result, in the pixel PIX in the first row, the charge corresponding to the gradation voltage Vdata is charged in the capacitor Cc of the pixel drive circuit DC.

  Next, in the second writing period Twb of the first row, the low-level selection signal Vsel1 is applied to the first selection line Ls1 of the first row of the display panel 110, and the high-level selection signal is applied to the second selection line Ls2. Vsel2 is applied, low level selection signals Vsel1 and Vsel2 are applied to the first and second selection lines Ls1 and Ls2 of the second to nth rows, and a low level (ground potential GND) power supply is applied to the power supply line La. With the voltage Vsa applied, the data line Ld of each column is set to the ground potential GND. Accordingly, in the pixel PIX in the first row, the charge corresponding to the write voltage Vdata ′ corresponding to the gradation voltage Vdata charged in the capacitor Cs of the pixel drive circuit DC and charged in the capacitor Cc in the first write period Twa. Is accumulated.

  Then, the series of operations for the pixels PIX in the first row are repeated for the pixels PIX in the second and subsequent rows as shown in FIG. Is written with a write voltage Vdata ′ corresponding to the image data.

  Next, as shown in FIG. 10, in the state where all the pixel collective light emission periods Taem are applied, the low-level selection signals Vsel1, Vsel2 are applied to the first and second selection lines Ls1, Ls2, and the high-level power supply is applied to the power supply line La. A voltage Vsa is applied. As a result, in all the rows of pixels PIX of the display panel 110, the light emission drive current Iem (drain current Ids) having a current value corresponding to the write voltage Vdata ′ flows through the transistor Tr13 which is the drive transistor of the pixel drive circuit DC. The organic EL element OEL of each pixel PIX emits light with a luminance gradation corresponding to the image data, and desired image information is displayed on the display panel 110.

  In other words, in the pixel drive circuit, the display device, and the drive control method thereof according to the present embodiment, the gradation of the voltage value corresponding to the image data is obtained using the AC coupling of the capacitor Cc during the image data write period. By directly applying the voltage Vdata between the gate and source of the driving transistor (transistor Tr13), a voltage designation type (or voltage application type) gradation control method for writing the gradation voltage Vdata into the capacitor Cs can be realized. it can.

  As a result, a write current corresponding to the image data is supplied, and the voltage component corresponding to the image data is held in the capacitor Cs connected between the gate and the source by the current / voltage conversion function of the drive transistor (transistor Tr13). Compared with the gradation control method, a gradation signal (gradation voltage) corresponding to image data can be reliably written to each pixel PIX.

Hereinafter, the operation and effect of the pixel drive circuit, the display device, and the drive control method thereof according to the present embodiment will be specifically described.
FIG. 11 is a circuit configuration diagram showing an example of a pixel as a comparison for explaining the superiority of the operation and effect of the pixel drive circuit and display device and the drive control method thereof according to the present invention. Here, about the structure equivalent to the pixel which concerns on this embodiment mentioned above, the same code | symbol is attached | subjected and the description is simplified or abbreviate | omitted.

  A pixel PIXa illustrated in FIG. 11 has a circuit configuration in which the capacitor Cc connected between the transistor Tr12 and the contact N12 is omitted from the pixel PIX (see FIG. 4) according to the present embodiment described above. That is, the contact N12 that is the source terminal of the transistor Tr13 is directly connected to the data line Ld via the transistor Tr12.

  In the drive control method in the pixel PIXa as shown in FIG. 11, first, in the writing period, a high level (selection level) selection signal Vsel is applied to the selection line Ls to turn on the transistors Tr11 and Tr12, and the power supply line A gradation signal corresponding to the image data is applied to the data line Ld in a state where a low level (ground potential GND) power supply voltage Vsa is applied to La.

  At this time, as the gradation signal, a negative gradation voltage Vdata corresponding to the image data is applied from the data driver (not shown) to the data line Ld, or the gradation current Idata corresponding to the image data is drawn by the data driver. As a result, a write current flows from the power supply line La in the direction of the data line Ld via the transistors Tr13 and Tr12.

  As a result, the voltage component corresponding to the image data is charged (written) in the capacitor Cs connected between the gate and source of the transistor Tr13 using the current / voltage conversion function of the transistor Tr13. At this time, since a potential lower than the common voltage Vcom (ground potential GND) applied to the cathode of the organic EL element OEL is set at the contact N12, no current flows through the organic EL element OEL and no light emission operation is performed.

  Next, in the light emission period, a low level (non-selection level) selection signal Vsel is applied to the selection line Ls to turn off the transistors Tr11 and Tr12, and a high level power supply voltage Vsa is applied to the power supply line La.

  Thus, the gate-source voltage Vgs (= Vdata) of the transistor Tr13 is held constant based on the voltage component charged in the capacitor Cs, and the light emission drive current Iem (in accordance with the gate-source voltage Vgs). A drain current Ids) flows from the power supply line La to the organic EL element OEL via the transistor Tr13. Here, since the current value of the light emission drive current Iem is defined by the voltage value of the gate-source voltage Vgs of the transistor Tr13, the organic EL element OEL emits light at a luminance gradation corresponding to the image data.

  By the way, in the pixel PIXa having the circuit configuration shown in FIG. 11, a gradation signal (gradation voltage Vdata or gradation current Idata) corresponding to image data is supplied during the writing operation, and the pixel driving circuit DC is written. Current is required. At this time, if there is a variation in the on-resistance of the transistor Tr12 (including a variation in on-resistance caused by a change in element characteristics over time), the voltage component written in each pixel PIXa also varies, and the image data corresponds to the image data. In other cases, the light emission operation cannot be performed with an appropriate luminance gradation, resulting in deterioration in image quality such as luminance unevenness.

  Further, in the pixel PIXa having the circuit configuration shown in FIG. 11, image data is supplied to the data line Ld in order to cause a write current to flow through the transistor Tr13 without causing the organic EL element OEL to emit light during the write operation. Therefore, it is necessary to apply a negative gradation voltage Vdata corresponding to or to draw the gradation current Idata in the data driver direction through the data line Ld. For this purpose, it is necessary to operate the data driver with a negative power supply, and the scale of the circuit block of the negative power supply high withstand voltage portion in the combined process of low withstand voltage and high withstand voltage of the data driver increases, In some cases, this increases costs.

  On the other hand, in the pixel drive circuit and display device and the drive control method thereof according to the present embodiment, as described above, a direct current cut (() is connected between the data line Ld and the source terminal of the drive transistor (transistor Tr13)). Alternatively, a capacitor Cc (as a coupling capacitor) is provided, and a drive transistor (transistor Tr13) is used without flowing a write current to the pixel drive circuit DC by using AC coupling of the capacitor Cc during a writing period of image data. The gradation voltage Vdata corresponding to the image data is written into the capacitor Cs between the gate and the source.

  As a result, an appropriate voltage component (gradation voltage Vdata) corresponding to the image data is written to each pixel PIX without being affected by variations in on-resistance of the transistors in the pixel drive circuit DC. In addition, the organic EL element OEL can be operated to emit light with an appropriate luminance gradation, and a good image quality without luminance unevenness can be realized.

  In particular, by applying amorphous silicon thin film transistors as the transistors Tr11 to Tr13 provided in the pixel drive circuit DC of each pixel PIX, the already established amorphous silicon manufacturing technology is applied, and the operation characteristics are uniform with a simple manufacturing process. Since a stable transistor can be realized, it is extremely effective in suppressing the above-described luminance unevenness and improving display image quality.

  In the display device and the drive control method thereof according to the present embodiment, the output circuit 145 of the data driver 140 is provided with the changeover switch 145a, and the positive voltage corresponding to the image data is applied to the data line Ld during the image data writing period. The gradation voltage Vdata is applied to the capacitor Cs between the gate and the source of the drive transistor (transistor Tr13), and then the gradation voltage Vdata corresponding to the image data is written. Yes.

  As a result, it is not necessary to operate the data driver 140 with a negative power supply, and the display panel 110 can be driven to display with a positive power supply. Therefore, the data driver 140 does not need to employ a high-voltage process with a negative power supply, and the driver chip. By reducing the size of the display device, it is possible to realize a narrow frame and cost reduction of the display device.

  In addition, prior to the display operation including the write operation and the light emission operation described above, a parameter for compensating for a change in the light emission characteristic of each pixel PIX (for example, a change in threshold voltage with time in the drive transistor of the pixel drive circuit). It is also possible to execute an operation of acquiring Specifically, for example, prior to the display operation, a predetermined test voltage is applied to each pixel PIX, whereby the luminance when the organic EL element OEL of each pixel PIX emits light is individually detected by the sensor, A parameter related to the light emission characteristic of the pixel PIX is acquired. Then, in the above-described writing operation, a gradation voltage Vdata is generated by adding a correction voltage component according to a variation in the light emission characteristics of each pixel based on the above parameter to a voltage component according to the image data, thereby generating a pixel PIX. Write to. Accordingly, each organic EL element OEL can be caused to emit light at an appropriate luminance gradation according to image data regardless of fluctuations in the light emission characteristics of each pixel PIX, and deterioration in display quality of the display panel 110 can be suppressed. be able to.

<Second Embodiment>
Next, a second embodiment in which the display device (light-emitting device) in the first embodiment is applied to an electronic device will be described with reference to the drawings. A display device 100 including a display panel 110 having a light emitting element composed of an organic EL element OEL in each pixel PIX can be applied to various electronic devices such as a digital camera, a mobile personal computer, and a mobile phone.

12 is a perspective view showing a configuration of a digital camera, FIG. 13 is a perspective view showing a configuration of a mobile personal computer, and FIG. 14 is a diagram showing a configuration of a mobile phone.
12, the digital camera 200 includes a main body unit 201, a lens unit 202, an operation unit 203, a display unit 204 including the display device 100 including the display panel 110 of the present embodiment, and a shutter button 205. Yes. In this case, in the display unit 204, the light emitting elements of the respective pixels of the display panel 110 can emit light with an appropriate luminance gradation according to the image data, so that a good and uniform image quality can be realized.

  In FIG. 13, the personal computer 210 includes a main body 211, a keyboard 212, and a display unit 213 including the display device 100 including the display panel 110 of the present embodiment. Even in this case, in the display unit 213, the light-emitting elements of the respective pixels of the display panel 110 can emit light at an appropriate luminance gradation according to the image data, thereby realizing good and uniform image quality.

  In FIG. 14, the mobile phone 220 includes an operation unit 221, an earpiece 222, a mouthpiece 223, and a display unit 224 including the display device 100 including the display panel 110 of the present embodiment. Even in this case, in the display unit 224, the light emitting elements of the respective pixels of the display panel 110 can emit light with an appropriate luminance gradation corresponding to the image data, thereby realizing a good and uniform image quality.

  In each of the above-described embodiments, the case where the present invention is applied to the display device 100 including the panel 110 having the light-emitting element including the organic EL element OEL in each pixel PIX has been described. However, the present invention is not limited to this. Absent. For example, a light emitting element array in which a plurality of pixels each having a light emitting element composed of an organic EL element OEL are arranged in one direction is provided, and exposure is performed by irradiating light emitted from the light emitting element array on a photosensitive drum according to image data. You may apply to an exposure apparatus. In this case, the light emitting element of each pixel of the light emitting element array can be caused to emit light at an appropriate luminance according to the image data, and a good exposure state can be obtained.

DESCRIPTION OF SYMBOLS 100 Display apparatus 110 Display panel 120 Selection driver 130 Power supply driver 140 Data driver 144 D / A converter 145 Output circuit 145a Changeover switch 145b Follower amplifier 150 System controller PIX Pixel DC pixel drive circuit Tr11-Tr14 Transistor Cs, Cc Capacitor OEL Organic EL element

Claims (12)

A pixel driving circuit for operating the light emitting element in a pixel having a light emitting element and connected to a data line,
A first capacitive element;
One end and the other end of the first capacitor element are connected to one end of the current path and a control terminal, and a driving current flowing in the current path according to the electric charge accumulated in the first capacitor element is supplied to the light emitting element. A drive control element to
A second capacitive element having one end connected to one end of the first capacitive element;
With
The first capacitive element has a second potential different from the first potential after the potential at the other end of the second capacitive element is set to a first potential corresponding to image data via the data line . charge corresponding to the image data by being set to a potential is accumulated,
The pixel driving circuit further controls conduction between one end of the second capacitor element and an electrode set to the second potential, and the other end of the second capacitor element has the first potential. when it is set to the pixel driving circuit according to claim Rukoto which have a reset control element for connecting the one end and the electrode of the second capacitor. A first selection control element that controls conduction between the other end of the current path of the drive control element and the control terminal;
The first selection control element is controlled to connect the other end of the current path of the drive control element and a control terminal when charge is accumulated in the first capacitor element and the second capacitor element. The pixel driving circuit according to claim 1, wherein: The reset control element, releases the connection between the one end and the electrode of said second capacitor when said second end of said second capacitor is set to the second potential from said first potential The pixel driving circuit according to claim 1 , wherein the pixel driving circuit is controlled so as to perform. And a second selection control element for controlling the conduction between the other end of the data line and the second capacitor,
It said second selection control element, when setting the other end of the second capacitor to the first potential, so as to connect the other end of the data line and the second capacitor the pixel driving circuit as claimed in any one of claims 1 to 3, characterized in that it is controlled. A light emitting device driven according to image data,
A light emitting panel having a plurality of pixels, and a plurality of data lines connected to the each pixel,
A drive circuit for driving the light emitting panel;
With
Each pixel includes a light emitting element, a first capacitor element, and one end and the other end of the first capacitor element connected to one end of a current path and a control terminal, and a charge accumulated in the first capacitor element. And a second capacitive element having one end connected to one end of the first capacitive element, and a first capacitive element connected to the first capacitive element. After the potential at the other end of the second capacitive element is set to the first potential corresponding to the image data via the data line, the capacitive element is set to a second potential different from the first potential. By setting, the charge corresponding to the image data is accumulated,
Each of the pixels further controls conduction between one end of the second capacitive element and the electrode set to the second potential, and the other end of the second capacitive element is set to the first potential. A reset control element for connecting one end of the second capacitor and the electrode when set;
Wherein the driving circuit, the data line by applying a voltage corresponding to the image data, set to the second potential a potential of the other end of the second capacitor after setting the first potential A light emitting device having a data driving circuit for performing the above operation. The data driving circuit includes a voltage generation circuit for generating a voltage according to the image data, and a connection switching circuit for switching and connecting the data line to the voltage generation circuit or the contact set to the second potential. The light-emitting device according to claim 5 . Wherein each pixel includes a first selection control element for controlling the conduction between the other end and the control terminal of the current path of the drive control device, the conduction between the other end of the data line and the second capacitor A second selection control element for controlling,
The drive circuit controls the first selection control element and the second selection control element to store charges in the first capacitance element and the second capacitance element, and the drive control element of connecting the other end to the control terminal of the current path, according to claim 5 or 6, characterized in that it has a selection drive circuit for connecting the other end of the said data line second capacitor Light emitting device. It said selection driving circuit controls the reset control element, the other end of the second capacitive element when setting the first potential, and the electrode and one end of said second capacitor connect, said other end of said second capacitive element to release the connection between the one end and the electrode of said second capacitor when being set to the second potential from said first potential The light-emitting device according to claim 7 . Electronic apparatus, characterized in that the light-emitting device according to any one of claims 5 to 8 is mounted. A drive control method of a light emitting device driven according to image data,
The light emitting device includes a light emitting element, a first capacitive element, and one end and the other end of the first capacitive element connected to one end of a current path and a control terminal, and a charge accumulated in the first capacitive element. And a plurality of pixels each having a drive control element that supplies a drive current flowing through the current path to the light emitting element, and a second capacitor element having one end connected to one end of the first capacitor element. Have a light-emitting panel,
A first writing operation step of setting the other end of the second capacitive element of each pixel to a first potential corresponding to the image data;
Setting said second end of said second capacitor of each pixel after setting the first potential, the other end of the second capacitor, the second potential different from said first potential A second writing operation step of storing charges corresponding to the image data in the first capacitive element;
A reset operation step for connecting one end of the second capacitor and the electrode set at the second potential, which is executed prior to the first write operation step;
A drive control method for a light-emitting device, comprising: The first writing step and the second write operation step includes a first connection operation step for connecting the other end of the data line and the second capacitor, the other current path of the drive control element The light emitting device drive control method according to claim 10 , further comprising a second connection operation step of connecting the end and the control terminal. The second write operation step, the drive control method of a light-emitting device according to claim 10 or 11, characterized in that it comprises a release operation step of releasing the connection between the one end and the electrode of said second capacitor .

Images