KR20070031917A - Display drive apparatus, display apparatus and drive control method thereof - Google Patents

Abstract

According to the display data, the display driving apparatus 130 for operating the current controlled optical element OEL each having the display pixel PX provided as the optical element OEL and the driving element Tr13 for supplying the driving current to the optical element. ) Is provided. The display driving apparatus includes a gray level signal generation circuit 130 for generating a gray level signal corresponding to the luminance gray level of the display, supplying the gray level signal to the display pixel, and a threshold voltage detection circuit for detecting an intrinsic threshold voltage of the driving element of the display pixel. 140, and a compensation voltage application circuit 150 for generating a compensation voltage for compensating the threshold voltage of the driving device based on the threshold voltage, and applying the compensation voltage to the driving device.

Driving element, optical element, display driving device, display pixel, compensation voltage, threshold voltage detection circuit, threshold voltage, luminance gradation, compensation voltage application circuit

Description

DISPLAY DRIVE APPARATUS, DISPLAY APPARATUS AND DRIVE CONTROL METHOD THEREOF}

The present invention relates to a display driving apparatus, a display apparatus having a display driving apparatus, and a driving method thereof, and more particularly, to a display panel configured by arranging a plurality of current controlled optical elements driven by supply of a current corresponding to display data. The present invention relates to a display driving apparatus to be applied, a display apparatus provided with the display driving apparatus, and a driving control method thereof.

In recent years, as a monitor and a display of a personal computer and a video device, the spread of the display apparatus of light weight and low power consumption is remarkable. In particular, liquid crystal displays (LCDs) are widely applied as display devices of portable devices (portable handsets) such as mobile phones, digital cameras, personal digital assistants (PDAs), and electronic dictionaries.

As a next-generation display device connecting an LCD device or the like, a display panel in which optical devices are arranged in a matrix, such as an organic electroluminescent device (organic EL device), a non-organic electroluminescent device (non-organic EL device), or a light emitting diode (LED), Research and development on the complete planarization of a self-luminous display device (self-luminous display) provided is being promoted.

In particular, the self-emission type display in which the active matrix driving mode is applied has a faster display response speed than the above-described liquid crystal display, has no dependency on viewing angle, enables high brightness / high contrast, high definition display quality, and the like, unlike LCD. Since no background lighting is required, the thickness and weight can be reduced and the power consumption can be reduced, which is extremely favorable for application to portable devices.

In addition, in such a self-luminous display, various drive control mechanisms and / or control methods for controlling the operation of light emitting devices have been proposed.

35 is a schematic structural diagram showing a main part of a conventional voltage controlled active matrix self-luminous display.

36 is an equivalent circuit showing a structural example of a display pixel applicable to a conventional self-luminous display.

35 shows a circuit configuration of a display pixel composed of a light emitting element having an organic EL element OEL as an optical element.

As shown in Fig. 35, the configuration of the conventional organic EL display device having the active matrix type includes: a plurality of scanning lines (selection lines) SLp arranged in the row direction and a plurality of data lines arranged in the column direction ( A display panel 110P including a plurality of display pixels EMp disposed in a matrix near the intersection of the signal lines DLp; A scan driver 120P connected to the scan line SLp; And a data driver 130P connected to the data line DL.

As shown in FIG. 36, each display pixel EMp may include a pixel driving circuit DCp. The circuit DCp is a thin film transistor (TEF, Tr111) and a contact point (N11) having a gate terminal connected to the scan line (SLp) and a source and drain terminal connected to the data line (DLp) and a contact point (N11), respectively. ) And a thin film transistor Tr112 having a source terminal connected to a predetermined power supply voltage Vdd. The organic EL element OEL has a positive terminal connected to the drain terminal D of the thin film transistor Tr112 in the pixel driving circuit DCp, and a negative terminal receiving a ground potential Vgnd lower than the power supply voltage Vdd. It may include. In FIG. 36, the symbol Cp denotes a capacitor configured between the gate and the source terminal of the thin film transistor Tr112.

In the display device including the display panel 110P constituted by the display pixels EMp, in order to turn on the thin film transistor Tr111 of the display pixels EMp and the driving circuit DCp in each row, first, On is turned on. The scan signal voltage Ssel of) -level is sequentially applied from the scan driver 120P to the scan line SLp of each row, thereby setting the display pixel EMp to the selected state.

At the same time as the setting to the selected state, a gray scale voltage Vpix having a voltage value corresponding to the display data is generated by the data driver 130P, is applied to the data lines DLp of each column, and then each display pixel ( It is applied to the contact point N11, ie, the gate terminal of the thin film transistor Tr112, via the thin film transistor Tr111 of EMp (driving circuit DC).

As a result, the thin film transistor Tr112 is turned on in a conductive state corresponding to the potential of the contact point N11 (in a precise sense, the potential difference between the gate and the source) (that is, the conductive state corresponding to the gradation voltage Vpix). Therefore, a predetermined driving current flows from the power supply voltage to the ground voltage Vgnd through the thin film transistor Tr112 and the organic EL element OEL. As a result, the organic EL element OEL emits light with a luminance gradation corresponding to the display data (gradation voltage Vpix).

Next, an off-level scan signal voltage Ssel is applied from the scan driver 120P to the scan line SLp. Accordingly, the thin film transistor Tr111 in the display pixels EMp of each row is turned off, the display pixels EMp are set to the non-selected state, and electrical conduction between the data line DLp and the driving circuit DCp is disconnected. At this time, the predetermined voltage is applied between the gate and the source terminal of the thin film transistor Tr112 based on the potential applied to the gate terminal (contact point N111) and held in the capacitor Cp. ) Stays on.

Therefore, in the same manner as the light emitting operation in the selected state, a predetermined drive current flows from the power supply voltage Vdd to the organic EL element OEL through the thin film transistor Tr112, thereby maintaining the light emitting operation. This light emission operation is controlled to continue for one frame period until, for example, the grayscale voltage Vpix corresponding to the next display data is applied (written) to the display pixels EMp in each row.

This driving control method is referred to as a voltage gradation specification mode (or voltage gradation regulation driving), and is applied to each display pixel EMp (more precisely, the gate terminal of the thin film transistor Tr112 of the driving circuit DCp). This is because the current value of the driving current flowing through the organic EL element OEL is controlled to perform the light emitting operation with a predetermined luminance gradation by adjusting the gradation voltage Vpix.

Since the current path is connected in series to the organic EL element OEL in the driving circuit DCp shown in Fig. 36, the thin film transistor Tr112 for driving for driving the driving current corresponding to the display data (gradation voltage) flows. Device characteristics (particularly threshold characteristics) may change (move) according to usage time, driving history, and the like. In this case, the relationship between the gate voltage (potential of the contact point N111) and the drive current (current between the source and drain terminals) flowing between the source and drain terminals is changed, thereby causing the drive current to flow at a predetermined gate voltage. The current value changes (for example, decreases). As a result, for a long time, it becomes difficult to realize the light emission operation with an appropriate luminance gradation that is stable and corresponds to the display data.

In addition, when the device characteristics (threshold voltages) of the thin film transistors Tr111 and Tr112 of the display panel 110P change with respect to each display pixel EMp and the driving circuit DCp according to each manufactured product. Alternatively, when a change occurs in the device characteristics (threshold voltages) of the thin film transistors Tr111 and Tr112 for each display panel 110P, the current of the driving current for each display pixel or each display panel in the driving circuit in the voltage gray scale mode. The value fluctuates greatly, making it impossible to perform appropriate gradation control.

Advantages of the present invention are to compensate for device characteristic variations and characteristic variations of the drive elements, display drive devices, display drive devices, display drive operations corresponding to display data, optical elements of displays provided with optical elements, and optical It is to provide a clear and uniform picture quality to a display device provided with a drive device for supplying a drive current to the device.

In order to obtain the above advantages, the display driving apparatus according to the present invention;

A gray level signal generating circuit for generating a gray level signal corresponding to the luminance gray level of the display data and supplying the gray level signal to the display pixel;

A threshold voltage detection circuit for detecting an intrinsic threshold voltage of the driving element of the display pixel; And

And a compensation voltage applying circuit configured to generate a compensation voltage compensating for the threshold voltage of the driving device based on the threshold voltage, and apply the compensation voltage to the driving device.

The display driving apparatus may further include a memory circuit corresponding to the threshold voltage and storing threshold data detected by the threshold voltage detection circuit.

The compensation voltage applying circuit generates a compensation voltage based on the threshold data stored in the memory circuit.

The display driving apparatus may further include a detection voltage applying circuit for applying a voltage for detecting the threshold value having a potential higher than the threshold voltage to the driving element. The drive element preferably includes a current path through which the drive current flows to the optical element and a control terminal for controlling the supply state of the drive current. The detection voltage application circuit applies the threshold detection voltage between the control terminal of the drive element and one end side of the current path. The threshold voltage detection circuit detects the potential difference between the control terminal of the drive element and one terminal side of the current path when no current flows in the current path as the threshold voltage. The compensation voltage application circuit applies a compensation voltage based on the threshold data stored in the memory circuit between the control terminal of the drive element and one end side of the current path.

The optical device may include a light emitting device that performs a light emitting operation at a luminance corresponding to a current value of an applied current. The gradation signal generating circuit is:

A gradation signal, comprising: a circuit for generating a gradation voltage having a current value for allowing the light emitting element to perform a light emitting operation at a luminance corresponding to the luminance gradation of display data; And a circuit for generating a non-light emitting display voltage having a predetermined voltage value for causing the light emitting element to perform a non-light emitting operation as a gray level signal.

The display driving apparatus includes a single data line provided corresponding to a display pixel, each signal path for detecting a threshold voltage by a threshold voltage detection circuit, each signal path for applying a compensation voltage to a compensation voltage application circuit, and a gray level signal generating circuit. At least one signal path switching circuit for selectively switching and controlling a connection between each signal path for supplying a gray level signal and a connection between a single data line and a signal path for applying a voltage for threshold detection to a detection voltage application circuit It may include.

In order to obtain the above advantages, the display device according to the present invention is:

A display panel having a display pixel including a current control optical element and a driving element for applying a driving current to the optical element at each intersection of the plurality of selection lines arranged in rows and the plurality of data lines arranged in columns; A selection driving unit which sequentially applies a selection signal to each of a plurality of selection lines of the display panel to sequentially set display pixels of each row to a selection state; A data driving unit for generating a signal gradation corresponding to the luminance gradation of the display data and including a gradation signal generation circuit for supplying the gradation signal to each display pixel through each data line; A threshold voltage detection circuit for detecting an intrinsic threshold voltage of a driving element of each display pixel through each data line; A compensation voltage applying circuit generating a compensation voltage to compensate the threshold voltage of each display pixel based on each threshold voltage, and applying the compensation voltage to each display pixel through each data line.

The data driving unit may further include a memory circuit that stores threshold data corresponding to the threshold voltage detected by the threshold voltage detection circuit. The compensation voltage applying circuit generates a compensation voltage based on the threshold data stored in the memory circuit. The data driving unit preferably further includes a detection voltage application circuit for applying a threshold detection voltage having a potential higher than the threshold voltage to the driving element of each display pixel through each data line. The driving device may include a current path through which a driving current flows to an optical device and a control terminal for controlling a supply state of the driving current. The detection voltage application circuit applies the threshold detection voltage between the control terminal of the drive element and one end side of the current path. The threshold voltage detection circuit detects a potential difference between the control terminal of the drive element and one end side of the current path when there is no current flow in the current path as a threshold voltage through each data line. The compensation voltage application circuit applies a compensation voltage based on the threshold data stored in the storage circuit between each control line of the driving element and one terminal side of the current path.

The optical element preferably further includes a light emitting element for performing the light emitting operation at a luminance corresponding to the current value of the applied current, wherein the optical element can be, for example, an organic EL element.

The gradation signal applying circuit;

A gradation signal, comprising: a circuit for generating a gradation current having a current value that enables the light emitting element to perform a light emitting operation at a luminance corresponding to the luminance gradation of display data; And a circuit for generating a non-light emitting display voltage having a predetermined voltage value for causing the light emitting element to perform a non-light emitting operation as a gray level signal.

The data drive unit is:

A threshold acquiring circuit for individually calling each threshold data corresponding to each threshold voltage detected from each of the plurality of display pixels through each data line, and sequentially transmitting each threshold data; And a data acquisition circuit which sequentially and individually retrieves or maintains the luminance tone data for generating the tone signal for each display pixel. The memory circuit individually stores each threshold data transmitted from the threshold acquisition circuit corresponding to each of the plurality of display pixels. The gradation signal generation circuit generates a gradation signal corresponding to the luminance gradation contained in the acquisition circuit, and supplies the gradation signal to each display pixel through each data line. The configuration for sequentially and individually loading luminance gradation data of the data acquisition circuit and the configuration for fetching and sequentially transmitting the threshold data of the threshold acquisition circuit are shared.

The data driving unit includes a single data line provided corresponding to the display pixel, each signal path for detecting the threshold voltage by the threshold voltage detection circuit, each signal path for applying the compensation voltage to the compensation voltage application circuit, and the gradation signal generating circuit. At least one signal path switching circuit for selectively switching and controlling a connection between each signal path for supplying a gray level signal and a connection between a single data line and a signal path for applying a voltage for threshold detection to a detection voltage application circuit It may include.

The display device preferably further includes a power supply driving unit for applying a predetermined power supply voltage to each of the plurality of display pixels. The power supply driving unit sequentially applies the power supply voltage to the display pixels of each row of the display panel at a predetermined time point, and sets the display pixels of each row to be in a driving state. Alternatively, the power driving unit divides the plurality of display pixels disposed on the display panel into sets of a plurality of rows, and then sequentially applies a power supply voltage to each of the obtained display pixel groups at a given point in time, thereby displaying each display. The pixel group can be set to a driving state.

The display device preferably further includes a drive control unit for generating a timing control signal for controlling the timing of the threshold voltage detection drive by the threshold voltage detection circuit. During each operation section in which the gradation signal is applied to all the plurality of display pixels arranged on the display panel by the selection driving unit and the data driving unit, the driving control unit has a threshold voltage detection circuit driving display pixels in different rows on the display panel. Control is performed with a timing control signal to detect the threshold voltage of the device. Alternatively, during each operation period in which the gradation signal is applied to all the plurality of display pixels disposed on the display panel by the selection driving unit and the data driving unit, the driving control unit is arranged in a row in which the threshold voltage detection circuit is close to the display panel. The control is performed with a timing control signal to detect the threshold voltage of the display pixel driving element of the.

In order to obtain these advantages, the drive control method of the display apparatus according to the present invention comprises: detecting a threshold voltage unique to each display pixel driving element on the display panel; Generating a compensation voltage for compensating the threshold voltage of the driving element based on the threshold voltage, applying the compensation voltage to the driving element of each display pixel, and maintaining the compensation voltage as a voltage component; Supplying a gradation signal to each display pixel, adding a voltage component based on the gradation signal to a voltage component based on the compensation voltage, and causing the driving element of each display pixel to maintain the voltage component; And supplying a driving current generated based on the voltage component held in the driving element of each display pixel to the optical element, and causing the optical element to operate in accordance with the gray level signal.

The threshold voltage detection operation step includes: applying a threshold detection voltage having a potential higher than the threshold voltage to a driving element of each display pixel; The threshold voltage may include detecting a voltage after a portion of the charge corresponding to the threshold detection voltage is discharged and converged.

The threshold voltage detection operation step may include an operation step of storing threshold data corresponding to the threshold voltage. The operation of storing the threshold data by detecting the threshold voltage includes, for each display pixel disposed on the display panel before the time of applying the compensation voltage to the driving element and maintaining the voltage component based on the gray level signal. Is performed. Alternatively, the threshold data storage operation by threshold voltage detection may be performed by driving display pixels of different rows disposed on the display panel during each operation period in which a gray level signal is applied to all display pixels disposed on the display panel. Is performed on the device. Alternatively, the operation of storing the threshold data by the threshold voltage detection is performed on the display pixel driving elements in the adjacent rows on the display panel during each operation period in which the gray level signal is applied to all the display pixels disposed on the display panel. do.

The operation step of adding the voltage component based on the gradation signal to the voltage component based on the compensation voltage and the operation step of allowing the driving element of each display pixel to maintain the voltage component are sequentially performed for the display pixels of each row arranged on the display panel. It can be performed as. It is preferable that the operation step of the optical element emitting light with a luminance gradation corresponding to the gradation signal is performed sequentially from each row in which the operation step of adding the voltage component based on the gradation signal to the voltage component based on the retained compensation voltage is finished. Do. Alternatively, the step of adding a voltage component based on the gray scale signal to the voltage component based on the gray scale signal and the step of allowing the driving element of each display pixel to maintain the voltage component may include: It may be performed sequentially for each display pixel group obtained by grouping on a row.

The operation step of causing the optical element to emit light with a luminance gradation corresponding to the gradation signal includes: an operation step of adding a voltage component based on the gradation signal to a voltage component based on the gradation signal, and a driving element of each display pixel to maintain the voltage component The operation step is performed sequentially from the group to be finished.

The optical element preferably includes a light emitting element that emits light with a luminance gradation corresponding to the current value of the applied current. The operation step of maintaining the voltage component based on the gradation signal includes: when the light emitting element of each display element is performed with the luminance corresponding to the gradation luminescence of the display data, as the gradation current, Generating a gradation current having a current value for enabling light emission operation at a luminance corresponding to gradation emission, and supplying the gradation current to a display pixel; When a non-light emitting operation is performed on the light emitting elements of each display element, as a gradation current, a non-light emitting display current having a predetermined voltage for causing the optical element to perform the non-light emitting operation is generated, and the non-light emitting display current Supplying to the display pixel.

1 is a diagram showing a configuration of part of an embodiment of a display device according to the present invention and a display pixel driven and controlled by the display drive device.

2 is a timing chart showing a threshold voltage detection operation of the display driving apparatus according to the present embodiment.

3 is a conceptual diagram illustrating a voltage application operation of the display driving apparatus according to the present embodiment.

4 is a conceptual diagram illustrating a voltage converging operation of the display driving apparatus according to the present embodiment.

5 is a conceptual diagram illustrating a voltage reading operation of the display driving apparatus according to the present embodiment.

FIG. 6 is a diagram showing an example of the current characteristics between the drain and the source when the voltage between the gate and the source is set to a predetermined condition and the voltage between the drain and the source is adjusted in the n-channel type thin film transistor.

7 is a timing chart showing a drive control method of the display driving apparatus according to the present embodiment.

8 is a conceptual diagram showing a pre-charging operation of the display driving apparatus according to the present embodiment.

9 is a conceptual diagram showing a data writing operation of the display driving apparatus according to the present embodiment.

10 is a conceptual diagram showing a light emitting operation of the display driving apparatus according to the present embodiment.

11 is a configuration diagram of a main part showing another structural example of the display driving apparatus according to the present embodiment.

12 is a timing chart showing a drive control method (non-light emitting operation) of the display driving apparatus according to the present embodiment.

13 is a conceptual diagram showing another example of the data writing operation of the display driving apparatus according to the present embodiment.

14 is a conceptual diagram illustrating a non-light emitting operation of the display driving apparatus according to the present embodiment.

15 is a schematic block diagram showing an example of the entire configuration of a display apparatus according to the present embodiment.

FIG. 16 is a schematic block diagram showing an example of a display panel applied to a display device and a peripheral circuit (selective driver, power driver) according to the present embodiment.

17 is a timing chart showing a first example of the drive control method of the display apparatus according to the present embodiment.

18 is a timing chart showing a second example of the drive control method for the display device according to the present embodiment.

Fig. 19 is a structural diagram of a principal part showing an example of a display device for realization of a second example of the drive control method for a display device according to the present embodiment.

20 is a timing chart showing a third example of the drive control method for the display apparatus according to the present embodiment.

21 is a timing chart showing the first modification of the second example of the drive control method for the display apparatus according to the present embodiment.

22 is a timing chart showing the first modification of the third example of the drive control method for the display device according to the present embodiment.

23 is a timing chart showing the second modification of the second example of the drive control method for the display device according to the present embodiment.

24 is a timing chart showing the second modification of the third example of the drive control method for the display apparatus according to the present embodiment.

25 is a timing chart showing a fourth example of the drive control method for the display device according to the present embodiment.

Fig. 26 is a structural diagram of an essential part showing an example of a display apparatus for realizing a fourth example of the drive control method for the display apparatus according to the present embodiment.

27 is a timing chart showing a fifth example of the drive control method for the display device according to the present embodiment.

28 is a timing chart showing a sixth example of the drive control method for the display apparatus according to the present embodiment.

29 is a timing chart showing a seventh example of the drive control method for the display device according to the present embodiment.

30 is a timing chart showing the first modification of the sixth example of the drive control method for the display device according to the present embodiment.

31 is a timing chart showing the first modification of the seventh example of the drive control method for the display apparatus according to the present embodiment.

32 is a timing chart showing the second modification of the sixth example of the drive control method for the display device according to the present embodiment.

33 is a timing chart showing the second modification of the seventh example of the drive control method for the display device according to the present embodiment.

34 is a timing chart showing an eighth example of the drive control method for the display device according to the present embodiment.

35 is a schematic structural diagram showing main parts of a conventional voltage controlled active matrix type self-luminous display.

36 is an equivalent circuit diagram showing a structural example of display pixels applied to a conventional self-luminous display.

Embodiments of a display driving apparatus, a display apparatus, and a driving control method according to the present invention are described in more detail with reference to the accompanying drawings.

First, a display driving apparatus and a driving control method applied to the display apparatus according to the present invention will be described with reference to the drawings.

1 is a schematic configuration diagram showing an embodiment of a display driving apparatus according to the present invention and one of a plurality of display pixels driven and controlled by the display driving apparatus.

The relationship between the display pixel disposed on the display panel of the display driver and the display driver for driving and controlling the display pixel will be described.

<Display Driver>

As shown in FIG. 1, the display driving apparatus 100 according to the present embodiment includes a shift register / data register unit 110, a display data latch unit 120, and a gradation signal generation unit (gradation signal generation circuit) 130. Threshold detection voltage analog-to-digital converter 140 (abbreviated as detection voltage (ADC) in the specification, denoted as Vth ADC in the drawing), threshold compensation voltage analog-to-digital converter (160, denoted as Vth DAC in the drawing) , Frame memory 170, and data line input / output switching unit 180.

The shift register / data register unit 110 (data acquisition circuit and threshold acquisition circuit) stores luminance tone data composed of a shift register for sequential movement signal output, and at least an externally supplied digital signal not shown in this figure. Contains data registers that are loaded sequentially.

More specifically, any one of the following three operations is performed sequentially. The first operation is an operation of reading display data (light-emitting gradation data) of the display pixels PX of one row of the display panel and transmitting them to the display data latch unit 120. The second operation sequentially reads the threshold voltages (threshold detection data) of the display pixels PX of one row held in the threshold data latch unit 160 and transfers the data to the frame memory 170. to be. The third operation is an operation of reading the threshold compensation data of the display pixel PX of a specific row from the frame memory 170 and transmitting the data to the threshold data latch unit 160. A detailed description of the three operations is given later.

The display data latch unit 120 holds display data (luminance gradation data) of one row of display pixels PX, which are loaded and transmitted from the outside by the shift register / data register unit 110.

The gradation signal generation unit (the gradation signal generation circuit 130) is a gradation signal for causing the organic EL element (current-controlled optical element) to perform light emission operation or non-light emission operation at a gradation luminance corresponding to display data. It selectively supplies one of (Idata) and non-luminous display voltage (Vzero). The current Idata has a predetermined current value for causing the organic EL element OEL to perform light emission operation with a predetermined luminance gradation. The display voltage Vzero has a predetermined voltage value at which the organic EL element OEL is set to a black display (minimum luminance gradation) state in which the non-light emitting operation, that is, the execution of the light emitting operation is not allowed.

Here, as an example of the configuration for supplying the gradation current having the current value corresponding to the display data as the gradation signal, the configuration is: power supply the digital signal voltage of each display data held in the display data latch unit 120 A digital-to-analog converter (D / A converter) for converting into an analog signal voltage based on a gray reference voltage supplied from a circuit (not shown); And a voltage-to-current converter for generating a gradation current Idata having a current value corresponding to the analog signal voltage.

A gradation display made by supplying a gradation current having a predetermined current value to each display pixel as the gradation voltage is described below. However, the present invention is not limited thereto. As the gradation voltage, any signal that allows the application of the gradation voltage having a voltage value corresponding to the display data is applicable. In this case, for example, a configuration including only a digital-analog converter is also applicable.

The detection voltage (threshold voltage detection circuit (ADC) 140) is an analog signal voltage, for example, driving current to a light emitting element such as an organic EL element OEL provided on each display pixel PX described below. The voltage component of the threshold voltage (or corresponding to the threshold voltage) of the switching element (thin film transistor Tr13) to be detected and retrieved, and the threshold voltage is converted into threshold detection data including the digital signal voltage.

The compensation voltage DAC 150, the compensation voltage application circuit, and the detection voltage application circuit convert the threshold compensation data having the digital signal voltage for compensation with respect to the threshold voltage of the switching element provided on each display pixel PX. Convert to a pre-charge voltage (threshold compensation voltage) with Further, as shown in the drive control method to be described later, the operation (threshold voltage detection operation) of measuring the threshold voltage of the switching element by the detection voltage ADC 140 is configured as follows. The predetermined detection voltage is output so that a potential difference higher than the threshold potential difference of the switching element is set (holding of the voltage component) between the gate and the source (both ends of the capacitor Cs) of the thin film transistor constituting the switching element.

In addition, the threshold data latch unit 160 sequentially performs one of the following operations. One operation loads and maintains threshold detection data converted and generated by the detection voltage ADC 140 for each display pixel PX in one row, and via the shift register / data register unit 110. The threshold detection data is sequentially transmitted to the frame memory 170 to be described later. Another operation sequentially loads and maintains threshold compensation data for each display pixel PX in one row corresponding to the threshold detection data from the frame memory 170, and stores the threshold compensation data in the compensation voltage (DAC) 150. ) Is the operation to transmit.

Also, before the operation of write display data (luminance gradation data) for each display pixel PX, the frame memory (memory circuit 170) is connected to the detection voltage (ADC 140) and the threshold data latch unit 160. Thereby sequentially loading threshold detection data based on the detected threshold voltage for each display pixel PX in one row through the shift register / data register unit 110; One screen (one frame) of the display panel while the frame memory sequentially outputs the threshold detection data through the shift register / data register unit 110 as the threshold compensation data or as the threshold compensation data corresponding to the threshold detection data. Sequentially store data for each display pixel PX in the array; Transfer the data to the threshold data latch unit 160 (compensation voltage (ADC) 150).

In addition, the data line input / output switching unit (signal path switching circuit 180); The threshold voltage of the switching element (thin film transistor) provided to each display pixel is read into the detection voltage ADC 140 via each data line DL provided in the column direction of the display panel, and the threshold voltage is measured. A voltage detecting side switch 181 for performing the operation; Supply the data line DL with a mode for supplying a pre-charge voltage to compensate for the threshold voltage of the switching element provided to each display pixel PX, or the luminance corresponding to each display pixel PX display data An input selection switch 182 for selecting at least one of supplying a gradation signal (gradation current or non-light-emitting display voltage) for performing light emission in the gradation; It may include a write-side switch (183) for supplying a gray level signal selected by the pre-charge voltage or the input signal selection switch 182 to each display pixel (PX).

The voltage detecting side switch 181 and the writing side switch 183 may be constituted by, for example, a thin film transistor (field effect transistor) having a different channel polarity. As shown in FIG. 1, a p-channel type thin film transistor may be applied to the voltage detecting side switch 181 and an n-channel type thin film transistor may be applied to the writing side switch 183. The gate terminal (control terminal) of the thin film transistor is connected to the same signal line, and the on-off state is controlled based on the signal level of the switching control signal AZ applied to the signal line.

<Display panel>

As shown in Fig. 1, the display pixel PX according to the present embodiment stores the organic EL element OEL which is a current controlled optical element and a driving current having a current value corresponding to the display data to the organic EL element OEL. It may include a driving circuit (DC) for supplying. The optical element and the driving circuit are disposed close to each intersection of the selection line SL arranged in the row direction (horizontal direction on the drawing) and the data line arranged in the column direction (vertical direction on the drawing) on each display panel.

The driving circuit DC may include the thin film transistors Tr11, Tr12, and Tr13 and the capacity C50. The transistor (second switch circuit, Tr11) may include a gate terminal (control terminal) connected to the selection line SL and a predetermined value. And a drain and a source terminal (both ends of the current path) connected to the power supply voltage line VL and the contact point N11, respectively, to receive the voltage Vsc of the transistor (the third switch circuit, Tr12). A gate terminal (control terminal) connected to the selection line SL, and a drain and source terminal (both ends of the current path) connected to the data line DL and the contact point N12, respectively. The switch circuit Tr13 has a gate terminal (control terminal) connected to the contact N11 and a drain and source terminal (both ends of the current path) connected to the power supply voltage line VL and the contact point (connection contact point N12), respectively. Capacitor C5 has contact point N11 and contact point N12. ) Is connected between the gate terminal and the source terminal of the thin film transistor Tr13, wherein the thin film transistor Tr13 is the detection voltage ADC 140 and the threshold data of the display driving apparatus 100 in which the threshold voltage is described above. Corresponds to the switching element for the drive being the measurement object by the latch unit 160.

The organic EL element OEL has a positive terminal connected to the contact point N12 of the driving circuit DC and a negative terminal to which the common voltage Vcom is applied. Here, during the write operation period in which a gradation signal (gradation current or non-light emitting display voltage) corresponding to the display data is applied to the driving circuit DC during the display driving operation to be described later, the common voltage Vcom is low potential (Vs). Has a potential equal to or higher than the power supply voltage Vsc. In addition, any voltage lower than the power supply voltage Vsc, which is set to a high potential Ve during the light emission operation section in which the light emission operation is performed at a predetermined luminance gradation while supplying the driving current to the organic EL element (optical element, OEL). The common voltage Vcom is set (for example, the ground potential GND) (Vs? Vcom <Ve).

Here, the capacitor Cs is a parasitic capacitance formed between the gate terminal and the source terminal of the thin film transistor Tr13, or in addition to the parasitic capacitance, the capacitance element is further connected in parallel between the contact point N11 and the contact point N12. It may be the capacitance at the point to be.

The thin film transistors Tr11 to Tr13 are not limited to a specific type. For example, it is preferable to apply an n-channel type amorphous silicon thin film transistor furnace to the thin film transistors (Tr11-Tr13). In this case, the driving circuit including the amorphous silicon thin film transistor having stable device characteristics (electron mobility, etc.) can be manufactured at a relatively low cost by applying the amorphous silicon process technology already established.

The case where all of the thin film transistors Tr11 to Tr13 are formed of n-channel thin film transistors will be described later. In addition, the optical element driven by the driving circuit DC is not limited to the organic EL element OEL, but may also be another light emitting element that meets the current controlled optical element, for example, a light emitting diode.

<Drive control method of display driving device and display pixel>

Subsequently, with respect to the display driving apparatus having the above-described structure, a driving control method (driving control operation) in the case where a gray scale display is made by the light emitting operation of the optical element of the display pixel will be described with reference to the drawings.

The driving control operation of the display driving apparatus 100 according to the present embodiment is performed before each display driving operation (pre-charging operation, writing operation, and light emitting operation. A threshold voltage detection operation step (threshold voltage detection section; first step) for measuring and storing the threshold voltage of the driving thin film transistor Tr13 (switching element; driving element) provided to the display pixel PX (driving circuit DC); And a driving thin film transistor Tr13 provided on each display pixel PX to maintain a voltage component (compensation for the threshold voltage) corresponding to the threshold voltage after the end of the threshold voltage detection operation, and a gray level corresponding to the display data. A display driving operation (display drive section) for writing a signal (gradation current having a predetermined current value) into the display data, and causing the organic EL element OEL to perform light emission with a required luminance gradation corresponding to the gradation signal; It may include.

Now, each control drive step will be described.

(Threshold voltage detection operation)

2 is a timing chart showing a threshold voltage detection operation of the display driving apparatus according to the present embodiment.

3 is a conceptual diagram illustrating a voltage application operation of the display driving apparatus according to the present embodiment.

4 is a conceptual diagram illustrating a voltage converging operation of the display driving apparatus according to the present embodiment.

5 is a conceptual diagram illustrating a voltage writing operation of the display driving apparatus according to the present embodiment.

Fig. 6 is a diagram showing an example of the current characteristics between the drain and the source when the voltage between the gate and the source is set to a predetermined condition and the voltage between the drain and the source is adjusted in the n-channel type thin film transistor.

As shown in FIG. 2, the threshold voltage detection operation of the display driving apparatus according to the present embodiment includes: a voltage for threshold voltage detection (detection voltage Vpv) within a predetermined threshold voltage detection period Tdec. The detection voltage between the gate and the source of the driving thin film transistor Tr13 applied from the shift register / data register unit 110 to the display pixel through the data line DLp and provided on the driving circuit DC of the display pixel ( A voltage application section (a detection voltage application step, Vpv) for holding a voltage component corresponding to Vpv) (accumulating charge corresponding to the detection voltage Vpv of the capacitor Cs); During the voltage application period Tpv, a part of the voltage component (charge accumulated in the capacitor Cs) held between the gate and the source of the thin film transistor Tr13 is discharged, and between the drain and the source of the thin film transistor Tr13 component. A voltage convergence section Tcv for maintaining only the voltage component (charge) corresponding to the threshold voltage of the current Ids (so that the voltage component (charge) remains in the capacitor Cs); After the voltage convergence period Tcv, the voltage component (voltage value based on the charge remaining in the capacitor Cs; the threshold voltage Vth13) held between the gate and the source of the thin film transistor Tr13 is measured, and the frame memory 170 It may include a voltage write interval (threshold voltage detection step, Trv) (Tdec ≥ Tpv + Tcv + Trv) for converting the measured value into digital data in order to store the data in a predetermined storage space.

Here, the threshold voltage Vth13 of the current Ids between the source and the gate of the thin film transistor Tr13 is further applied by a minimum voltage between the drain and the source, so that the current Ids becomes the drain and the source of the thin film transistor Tr13. The voltage Vgs between the gate and the source of the thin film transistor Tr13 forming an operating boundary which is a point at which flow starts to flow therebetween. In particular, the threshold voltage Vth13 measured during the voltage write-in period Trv according to the present embodiment is a change occurring in the threshold voltage in the initial process state of the thin film transistor Tr13 by driving history (luminance history), usage time, etc. Vth shift), the threshold voltage at the time point of performing the threshold voltage detection operation is presented.

Each operation section associated with the threshold voltage detection operation will then be described in more detail.

(Voltage application section)

First, as shown in Figs. 2 and 3, during the voltage application period Tpv, while the low-potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL, the on-level (high- Level) selection signal Ssel is applied to the selection line SL of the driving circuit DC. Here, the low-potential power supply Vsc = Vs may be equal to or lower than the common voltage Vcom, and may be, for example, the ground potential GND.

At the same time, on the other hand, the switching control signal AZ is set to a high level so that the write-side switch 183 is turned on while the input selection switch 182 is switched to the compensation voltage (circuit (DAC) 150) side. In the (On) state, the voltage detecting side switch 181 is set to the off state. As a result, the detection voltage Vpv of the threshold voltage output from the compensation voltage DAC 150 is transferred via the data line input / output switching unit 180 (input selection switch 182 and write-side switch 183). Is applied to the line DL.

As a result, the thin film transistors Tr11 and Tr12 provided to the driving circuit DC constituting the display pixel are turned on. Accordingly, the power supply voltage Vsc is applied to the gate terminal of the thin film transistor Tr13 and one end side of the capacitor Cp (contact point N11) through the thin film transistor Tr11, and to the data line DL. The applied detection voltage Vpv is applied to the source terminal of the thin film transistor Tr13 and the other end side of the capacitor Cs (contact point N12) through the thin film transistor Tr12.

Here, at the time of the predetermined voltage Ids between the source and the drain for the n-channel type thin film transistor Tr13 for supplying a driving current to the organic EL element OEL of the display pixel (driving circuit DC). When the voltage Vds between the drain and the source is adjusted, the current change characteristic between the drain and the source can be seen in FIG. 6.

계조전류)의 증가에 따라 점차적으로 증가한다.In FIG. 6, the horizontal axis shows the divided voltage of the thin film transistor Tr13 and the divided voltage of the organic EL element OEL connected in series, and the vertical axis shows the current of the current Ids between the drain and the source of the thin film transistor Tr13. Show the value. In Fig. 6, the chain line shows the boundary of the threshold voltage between the gate and the drain of the thin film transistor Tr13. The left border shows the unsaturated region and the right shows the saturated region. While the voltage Vds between the gate and the source of the thin film transistor Tr13 emits light at the maximum brightness gradation, the voltage Vgs1 and Vgs <are applied to the voltage Vgsmax while emitting light at any brightness other than the maximum brightness gradation. When each of Vgs1 &lt; Vgsmax is fixed, the change characteristic of the current Ids between the drain and the source at the time of the adjustment of the voltage Vds between the drain and the source of the thin film transistor Tr13 is indicated by a thick line. The dotted line shows the load characteristic line EL (load line) when the light emitting operation is performed on the organic EL element OEL. The voltage on the right side of the organic EL element OEL load line becomes the divided voltage of the organic EL element OEL at a voltage between the power supply voltage Vsc and the common power Vcom, for example, 20V in FIG. 6. The voltage on the left side of the organic EL element OEL coincides with the voltage Vds between the drain and the source of the thin film transistor Tr13. The divided voltage of the organic EL element OEL increases the gray level luminance, that is, the current Ids, the driving current between the drain and the source of the thin film transistor Tr13.

It gradually increases with the increase of the gradation current.

In the unsaturated region of FIG. 6, even when the voltage Vgs between the gate and the source of the thin film transistor Tr13 is set to a definite level, the current value of the current Ids between the drain and the source is thin film in the inactive region. The voltage Vds between the drain and the source of the transistor Tr13 increases significantly (changes). On the other hand, in the saturation region, when the voltage Vgs between the gate and the source of the thin film transistor Tr13 is set to a definite level, the current Ids between the drain and the source of the thin film transistor Tr13 does not increase significantly. The increase in the voltage Vds between the drain and the source in the saturation region is also set at a limited level.

Here, in the characteristic diagram shown in FIG. 6, the voltage Vgs between the gate and the source of the thin film transistor Tr13 is set to a value of the voltage Vds that can be obtained between the drain and the source of the region showing saturation characteristics. During the voltage application period Tpv, the compensation voltage (circuit, DAC, 150) is applied to the data line DL (display pixel (which is further applied to the source terminal of the thin film transistor Tr13 of the driving circuit DC). The detection voltage Vpv is sufficiently lower than the power supply voltage Vsc = Vs set to a low potential In an embodiment of the present invention, as the detection voltage Vgv, for example, the maximum voltage is the compensation voltage DAC 150. From, can be set to be applied to the data line (DL).

The detection voltage Vpv is set to satisfy the following equation (1).

| Vs-Vpv | > Vth12 + Vth13

In Equation (1), the reference symbol Vth12 means a threshold voltage between the drain and the source of the thin film transistor Tr12 when the on-level select signal Ssel is applied to the gate terminal of the transistor Tr12. . In addition, the low-potential power supply voltage Vsc is applied to both the gate and drain terminals of the thin film transistor Tr13 so that the two potentials coincide with each other. Accordingly, Vth13 may be a threshold voltage of the voltage between the drain and the source of the transistor Tr13, and may also be a threshold voltage between the gate and the source of the thin film transistor Tr13. Here, although Vth12 + Vth13 gradually increases as time passes, the potential difference of (Vs-Vpv) is set high to always satisfy Equation (1).

In this manner, the potential difference Vcp (potential between both ends) higher than the threshold voltage Vth13 of the thin film transistor Tr13 is between the gate and the source of the thin film transistor Tr13 (that is, both terminal sides of the capacitor Cs). ), Whereby the detection current Ipv having a large current corresponding to the voltage Vcp is supplied from the power supply voltage line VL through the drain and source of the thin film transistor Tr13 to the compensation voltage (circuit DAC). 150) forcibly. As a result, charges corresponding to the potential difference based on the detection current Ipv rapidly accumulate on both ends of the capacitor Cs (that is, the voltage Vcp accumulates in the capacitor Cs). Incidentally, not only charge is accumulated in the capacitor Cs during the voltage application period Vpv, but also charge is detected in other capacitive components in the current path from the power supply voltage line VL to the data line DL. Accumulate for the flow of Ipv).

At this time, since the common voltage Vcom = GND equal to or higher than the low-potential power supply voltage Vsc = Vs applied to the power supply voltage line VL is applied to the cathode terminal of the organic EL element OEL, the organic EL element ( The point between the cathode and the anode of the OEL is set to a non-electrical electric field state or a reverse bias state, so that no driving current flows to the organic EL element OEL and no light emission operation is performed.

(Voltage convergence section)

Next, during the voltage convergence period Tcv after the end of the voltage application period Tpv, the on-level selection signal Ssel is applied to the selection line SL, as shown in FIGS. 2 and 3. Further, in a state where the low-potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL, the switching control signal AZ is set to the low-level, and as a result, the write-side switch 183 is turned off. While being set to the state, the voltage detecting side switch 181 is set to the on state. In addition, the output of the detection voltage Vpv from the compensation voltage DAC 150 is delayed. As a result, the thin film transistors Tr11 and Tr12 are kept in the on state, and thus the electrical conduction state of the display pixel (the driving circuit DC with the data line DL of the driving circuit DC is preserved.) However, the other end of the capacitor Cs is preserved. The side (contact point N12) is set to high impedance after the application of voltage to the data line DL is blocked.

At this time, the gate voltage of the thin film transistor Tr13 is preserved as the charge (both terminal potentials Vc = Vcp> Vth13) accumulated in the capacitor Cs during the voltage application period Tpv. Therefore, the thin film transistor Tr13 is kept in the on state, and current flows continuously between the drain and the source. As a result, the potential on one side of the source terminal of the thin film transistor Tr13 (contact point N12; the other end side of the capacitor Cs) has a potential at the drain terminal side (the power supply voltage line VL side). Gradually rises as you approach.

In this manner, part of the charge accumulated in the capacitor Cs is discharged, and the voltage Vgs between the gate and the source of the thin film transistor Tr13 is reduced. As a result, the voltage Vgs changes to converge to the threshold voltage Vth13 of the thin film transistor Tr13. As a result, the current Ids between the gate and the source of the thin film transistor Tr13 is reduced, and as a result, the current flow is delayed.

Also during this voltage convergence period Tvc, the potential of the cathode terminal of the organic EL element OEL has a potential equal to or less than the common voltage Vcom on the cathode terminal side. For this reason, no voltage is applied to the organic EL element OEL or a reverse bias voltage is applied to the organic EL element OEL. Therefore, the organic EL element OEL does not perform any light emitting operation.

(Voltage reading section)

Next, as shown in Figs. 2 and 5, during the voltage writing section Trv after the voltage convergence section Tcv has elapsed, the on-level selection signal Ssel is applied to the selection line SL, and the low- The potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL, and during the voltage convergence period Tcv in this state, the switching control signal AZ is set to the low-level, and the data The potential (detection voltage Vpv) of the line DL is measured by the threshold data latch unit 160 which is in electrical communication with the detection voltage ADC 140 and the data line DL.

Here, the data line DL after the voltage convergence period Tcv has been connected to the source terminal side (contact point N12) of the thin film transistor Tr13 through the thin film transistor Tr12 set to the on state. Is set. In addition, as described above, the potential of the source terminal side (contact point N12) of the thin film transistor Tr13 is equal to that of the capacitor Cs in which charge corresponding to the threshold voltage Vth13 of the thin film transistor Tr13 is accumulated. Coincides with the potential on the other end side.

The potential at the gate terminal side (contact point N11) of the thin film transistor Tr13 is the potential on one terminal side of the capacitor Cs in which charge corresponding to the threshold voltage Vth13 of the thin film transistor Tr13 is accumulated. At this time, the potential is set to a state connected to the low-potential power supply voltage Vsc through the thin film transistor Tr11 set to the on state.

As a result, the potential of the data line DL measured by the detection voltage ADC 140 coincides with the potential on the source terminal side of the thin film transistor Tr13 or a potential corresponding thereto. Therefore, the voltage Vgs between the gate and the source of the thin film transistor Tr13 (potential at both ends of the capacitor Cs) is detected, that is, the threshold voltage Vth13 or the detection voltage Vdec of the thin film transistor Tr13. Threshold voltage Vth13 or threshold voltage (Vth13) of the thin film transistor Tr13 based on the difference (potential difference) between the low-potential power supply voltage Vsc (e.g., the ground potential GND), which is accurately set in advance as It is possible to detect the voltage corresponding to Vth13).

The threshold voltage Vth13 (analog signal voltage) of the thin film transistor Tr13 detected in this manner is converted into threshold detection data including the digital signal voltage by the detection voltage ADC 140 and the threshold data latch unit 160. Is temporarily held, and subsequent reading of the threshold detection data of each display pixel in one row to be stored in a predetermined memory area of the frame memory 170 after the threshold data latch unit 160 is followed sequentially. Here, after the threshold voltage Vth13 of the thin film transistor Tr13 provided on the driving circuit DC of each display pixel has a different degree of change (Vth shift) due to the driving history (luminance history) or the like, each display Intrinsic threshold detection data of a pixel is stored in the frame memory 170.

(Display drive operation: gradation display operation)

7 is a timing chart showing a drive control method of the display driving apparatus according to the present embodiment.

8 is a conceptual diagram showing a pre-charging operation of the display driving apparatus according to the present embodiment.

9 is a conceptual diagram showing a data writing operation of the display driving apparatus according to the present embodiment.

10 is a conceptual diagram showing a light emitting operation of the display driving apparatus according to the present embodiment.

As shown in FIG. 7, the display driving operation of the display driving apparatus according to the present exemplary embodiment includes: a display pixel from the display driving apparatus 100 through the data line DL in the display driving section ( one processing cycle section ). A predetermined pre-charge voltage Vpre is applied to PX, and a voltage component corresponding to the threshold voltage Vth13 of the current Ids between the drain and the source of the thin film transistor Tr13 is applied to the display pixel PX. A pre-charge section is maintained between the gate and the source of the driving thin film transistor Tr13 provided on the driving circuit DC (accumulates and discharges the charge in the capacitor Cs), and compensates for the threshold voltage. Step 2. applying a compensation voltage, Tth); Applying a gradation signal (gradation current) corresponding to the display data, adding a voltage component corresponding to the gradation signal to a voltage component corresponding to the threshold voltage Vth13 maintained during the pre-charge section Tth, and A writing operation section for writing between the gate and the source of the thin film transistor Tr13 (third step; data writing step, Twrt); And a driving current having a current value corresponding to the display data based on all voltage components (total charge accumulated in the capacitor Cs) held between the gate and the source of the thin film transistor Tr13, to the organic EL element OEL. By making it flow, it is set to include a light emission operation section (gradation luminance step, Tem) (Tcyc? Tth + Twrt + Tem) which emits light with a predetermined luminance gradation.

Here, one processing cycle section applied to the display driving section Tcyc according to the present exemplary embodiment is set to a section in which the display pixel PX is required to display image information of one pixel from one frame image. That is, as described in the driving control method of the display device to be followed, one processing cycle section is displayed when one frame image is displayed on a display panel including a plurality of display pixels PX arranged in a matrix configuration in a row and column direction. The display pixel PX of one row is set to a section required to display an image of one row from one frame image.

Hereinafter, the driving section associated with each display driving operation will be described in more detail.

(Pre-charge section)

As shown in Figs. 7 and 8, first, during the pre-charge section Tth, the on-level (high level) selection signal Ssel is driven in the same manner as the voltage application section Tpv. And a low-potential power supply voltage (Vsc = Vs, for example ground potential GND) is applied to the power supply voltage line VL.

As a result, the thin film transistors Tr11 and Tr12 provided to the driving circuit DC are turned on, and the source terminal (contact point N12) of the thin film transistor Tr13 is connected to the data line DL through the thin film transistor Tr12. During the electrical conduction, the power supply voltage Vsc is applied to the gate terminal (contact point N11; one end side of the capacitor Cs) of the thin film transistor Tr13 through the thin film transistor Tr11.

At the same time, on the other hand, the switching control signal AZ is set to a high level, and the write-side switch 183 is set to the on state. The voltage detection side switch 181 is set to the off state while the input selection switch 182 is turned on and set to the side of the compensation voltage DAC 150.

In this way, the pre-charge voltage Vpre output from the compensation voltage DAC 150 causes the data line input / output switch unit 180 (the input selection switch 182 and the write-side switch 183) to fall. It is applied to the data line DL through. In addition, the pre-charge voltage Vpre is applied to the source terminal (contact point N12) of the thin film transistor Tr13 through the thin film transistor Tr12 provided to the driving circuit DC.

Here, during the pre-charge period Tth, the source terminal (contact point) of the display pixel PX (drive circuit DC) thin film transistor Tr13 from the compensation voltage DAC 150 through the data line DL. The pre-charge voltage Vpre applied to (N12) is detected for each display pixel PX during the threshold voltage detection operation by the detection voltage ADC 140 and the threshold data latch unit 160. Based on the threshold detection data stored separately in the frame memory 170 for each display pixel PX, the pre-charge voltage is intrinsic to the thin film transistor Tr13 of each display pixel PX (driving circuit DC). Has a current value for compensating for the threshold voltage Vth13. The application of the pre-charge voltage Vpre sets the voltage value to maintain the voltage component corresponding to the threshold voltage Vth13 between the gate and the source of the thin film transistor Tr13 (both ends of the capacitor Cs). do.

The threshold voltage Vth13 of the thin film transistor Tr13 will be described in more detail. As described above, n− is applied to the thin film transistors Tr11 to Tr13 constituting the driving circuit DC provided on the display pixel PX. In the case of applying the channel-type amorphous silicon thin film transistor furnace, a thin film transistor having uniform device characteristics can be formed by applying an already established amorphous silicon process technology, and a driving circuit having stable device characteristics is relatively easy. The advantage would be that it can be manufactured in a process.

However, it is known that a gradual change in the threshold voltage (Vth shift) occurs significantly due to the driving history of the amorphous silicon thin film transistor. As a driving control method for suppressing the influence of the change in the threshold voltage, the driving circuit DC provided on the display pixel PX via the data line DL is provided with the current component (gradation current) of the gray level signal corresponding to the display data. A drive control method of the current gradation regulation mode (or the current gradation regulation driving section) which flows directly toward the side is known. In such a drive control method, a (parasitic) capacitive element formed even on a channel applied with a gradation current is added to the point between the gate and the source (both ends of the capacitor Cs) of the driving thin film transistor Tr13 in addition to the gradation. It is charged to a predetermined voltage by the current. For this reason, in the case where the light emission operation (low gradation display) is performed with low luminance gradation, the charging operation takes a considerable time, the writing operation of the gradation signal does not end at a predetermined time, and the thin film transistor Tr13 Since the voltage component held between the gate and the source (both ends of the capacitor Cs) is not sufficient for the display data and writing is insufficient, there is a possibility that the light emitting operation is not performed with the required luminance gradation.

More specifically, in the drive control method of the current control prescribed mode, the thin film transistor Tr13 required to flow a gradation current corresponding to the display data between the drain and the source of the thin film transistor Tr13 during the write operation to be described later. Many voltage components from the voltage Vgs between the gate and the source contribute to the threshold voltage Vth13 of the thin film transistor Tr13. In particular, at the voltage Vlsb between the gate and the source of the thin film transistor Tr13, which is the voltage required for the organic EL element OEL to perform light emission with the minimum luminance gray scale LSB, The results of each experiment are classified as the ratio of the voltage component contributing to the threshold voltage Vth13 is 50% or more.

The threshold value between the gate and the source in the write operation of only the gradation signal (the gradation current having one instantaneous current value) without the application of the pre-charge operation (application of the pre-charge voltage Vpre) according to the present embodiment. When attempting to charge the voltage component (charge capacity) corresponding to the voltage Vth13, the write operation section Twrt to be described later is extended so that the image information is advantageous for a predetermined processing section (one frame section). There have been drawbacks that result in not being displayed.

Therefore, in this embodiment, the pre-charge section Tth is provided to apply the pre-charge voltage Vpre before the write operation of the gradation signal to be described later. As a result, a voltage component corresponding to the threshold voltage Vth13 at the current point of the thin film transistor Tr13 (threshold voltage at the time of detecting the threshold voltage after the Vth movement due to the driving history) is formed between the gate and the source of the thin film transistor Tr13 ( It is set in the state hold | maintained at both terminal side of capacitor Cs. Incidentally, with the gray level signal, or even have a fine gradation current of low gray scale display, a thin film transistor (Tr13) gate and a thin film transistor (Tr13), without charging the voltage component corresponding to the threshold value voltage (Vth13) between the source of The voltage component (the actual voltage component for the gradation display corresponding to the display data, except for the portion of the threshold voltage Vth13; the effect voltage Vdata) is applied to the threshold voltage Vth13 so that it can be maintained between the gate and the source. It is added to the corresponding voltage component.

During the pre-charge period Tth, the voltage component corresponding to the intrinsic threshold voltage Vth13 of the thin film transistor Tr13 is controlled to be set to be maintained between the gate and the source of the thin film transistor Tr13. For this reason, the current flows slightly between the gate and the source of the thin film transistor Tr13. The potential on the cathode terminal (contact point N11) side of the organic EL element OEL is equal to or less than the common voltage Vcom on the cathode terminal side. Therefore, no voltage is applied to the organic EL element OEL or a reverse bias is applied to the organic EL element OEL so that the organic EL element OEL does not perform light emitting operation.

In this way, in order to maintain the voltage component corresponding to the threshold voltage Vth13 between the gate and the source of the thin film transistor Tr13, a voltage value corresponding to the intrinsic threshold voltage Vth13 of each thin film transistor Tr13 is obtained. The pre-charge voltage Vpre having is applied directly to the source terminal side (contact point N11) without the flow of current based on the voltage components of the drive circuit DC and data line DL. Therefore, the voltage component corresponding to the threshold voltage Vth13 can be quickly charged in the driving thin film transistor Tr13 (capacitor Cs) of each display pixel PX (driving circuit DC).

(Writing operation section)

Next, as shown in FIGS. 7 and 9, after the pre-charge period Tth, the on-level select signal Ssel is applied to the select line SL during the write operation period Twrt. The low-potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL. As a result, in the state where the switching control signal AZ is set to a high level, the input selection switch 182 is turned on, and is set on the gradation signal generating unit 130 side, corresponding to the display data, and the gradation signal generating unit 130. Output of the gradation signal (the gradation current (Idata) having a negative polarity) is output through the data line input / output switch unit 180, the input selection switch 182, and the write-side switch 183. Is applied. Here, the gradation current Idata having a negative polarity is supplied as a negative signal, so that current is supplied from the data line DL side of the gradation signal generating unit 130 through the data line input / output switch unit 180. The gray level is generated in the direction of the signal generating unit 130.

As a result, after the thin film transistor Tr11 provided on the display pixel PX is turned on, the low-potential power supply voltage Vsc = Vs passes through the thin film transistor Tr11 to the gate and the capacitor (Tr13). Cs) is applied to one terminal side (contact point N11). In addition, the thin film transistor Tr12 is turned on, and the gradation current Idata flows in through the data line DL, whereby a voltage having a potential lower than the power supply voltage Vsc is applied to the source terminal of the thin film transistor Tr13. Is applied to the contact point N12 (another end side of the capacitor Cs). As a result, the thin film transistor Tr13 is turned on in a predetermined conduction state, and as shown in FIG. 9, the write current Iwrt corresponding to the current value of the gradation current Idata is moved from the power supply voltage line VL to the thin film transistor. It rapidly flows to the display driving apparatus 100 through the Tr13, the contact point N12, the thin film transistor Tr12, and the data line DL.

Here, in the capacitor Cs connected between the gate and the source of the thin film transistor Tr13, a voltage component corresponding to the intrinsic threshold voltage Vth13 of the thin film transistor Tr13 has a pre-charge section Tth, in which charge is accumulated. Is set to a state that is maintained. Therefore, the electric charge of the capacitance required to write the current Iwrt based on the gradation current Idata set in a fixed state between the drain and the source of the thin film transistor Tr13 does not include the threshold voltage Vth13. The charge may be a gradation current (Idata) having a current value for charging the effect voltage (Vdata) for providing the gradation display only according to the display data, and the charge is a gate and a source of the thin film transistor (Tr13) for a relatively short time. Can be charged in between.

Therefore, even when the threshold voltage Vth13 of the thin film transistor Tr13 is shifted (Vth) having a light emission history (drive history) or the like, the voltage component Vdata corresponding to the gradation signal (display data) is written. It can be written quickly and sufficiently during the interval Twrt. Incidentally, during the write operation period Twrt, the voltage Vgs between the gate and the source of the thin film transistor Tr13, that is, the amount of charge accumulated in the capacitor Cs is equal to the current between the source and the drain of the thin film transistor Tr13. As a result, the voltage Vc charged in the capacitor Cs is a voltage component corresponding to the intrinsic threshold voltage Vth13 of the thin film transistor Tr13 (effect voltage, Vdata). ) And the total of the gradation current Idata (Vth13 + Vdata).

At this time, the low-potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL, and the current (in the direction of the data line DL from the power supply voltage line VL through the driving circuit DC). After the write current Iwrt is controlled in such a manner that Iwrt flows, the potential applied to the cathode terminal (contact point N12) of the organic EL element OEL is equal to or smaller than the potentials Vcom and GND of the cathode terminal. . For this reason, a reverse bias voltage is applied to the organic EL element OEL so that the driving current does not flow through the organic EL element OEL and no light emitting operation is performed.

(Light emitting operation section)

Next, as shown in FIGS. 7 and 10, during the light emitting operation section Tem after the end of the writing operation section Twrt, the off-level (low level) selection signal Ssel is applied to the selection line SL. And a high-potential power supply voltage Vsc = Vs is applied to the power supply voltage line VL. At the same time, the operation of introducing the gradation current Idata by the gradation signal generation unit 130 is delayed.

As a result, the thin film transistors Tr11 and Tr12 provided to the driving circuit DC are turned on, and the electrical conduction between the data line DL and the source terminal (contact point N12; another end side of the capacitor Cs) is turned on. During this disconnection, the application of the power supply voltage Vsc to the gate terminal (contact point N11; one end side of the capacitor Cs) and the drain terminal is blocked. As a result, the charge accumulated in the capacitor Cs is maintained during the write operation period Twrt.

During the light emitting operation period Tem, the high potential power supply voltage Vsc = Ve applied to the power supply voltage line VL is required when the organic EL element OEL performs the light emission operation at the maximum gray scale MSB. It is set in such a manner as to be a voltage value (anode voltage serving as a forward bias with respect to the voltage Vcom connected to the cathode side of the organic EL element OEL) which is not smaller than the cathode voltage value.

In particular, the high-potential power supply voltage (Vsc = Ve) is set to a voltage value that satisfies the following equation (2).

| Ve-Vcom | > Vdsmax + Velmax

In Equation (2), the reference symbol (vdsmax) is the maximum voltage between the drain and the source of the thin film transistor (Tr13), that is, the light emission operation when the gradation current (Idata) flows during the light emission operation at the maximum brightness gradation During the (Tem) period, it means the voltage between the drain and the source reaching the saturation region shown in FIG. In addition, the reference symbol Velmax means the divided voltage of the organic EL element OEL at the time of maximum luminance gradation.

In this way, the sum Vth13 + Vdata of the total voltage components charged to the capacitor Cs at the time of the pre-charge operation and the write operation is maintained as both terminal side potentials Vc of the capacitor Cs. As a result, the voltage Vgs between the gate and the source of the thin film transistor Tr13 (that is, the potential of the contact point N11) is maintained as a result of keeping the thin film transistor Tr13 turned on.

wrt = Idata)을 갖는다. 결과적으로, 소정의 발광 상태(휘도계조)에 상응하는 구동전류(Iem)가 기입동작 구간(Twrt) 동안 기입된 전압성분(효과 전압(Vdata))에 기초하여 인가되고, 유기 EL 소자(OEL)가 디스플레이 데이터(계조신호)에 상응하는 휘도계조로 발광한다.Accordingly, as shown in FIG. 10, during the light emitting operation period Tem, the driving current Iem is transferred from the power supply voltage line VL to the organic EL element OEL through the thin film transistor Tr13 and the contact point N12. Direction, and the organic EL element OEL emits light with a predetermined luminance gradation corresponding to the current value of the drive current Iem. Here, during the light emission operation period, the charge (both tip potential Vc) held in the capacitor Cs is caused to flow in the above-described thin film transistor Tr13 so that the write current Iwrt coinciding with the gradation current Idata flows. This is consistent with the potential difference when Therefore, the drive current Iem flowing through the organic EL element OEL is equal to the current value Iem corresponding to the write current Iwrt and gradation current Idata.

wrt = Idata). As a result, the drive current Iem corresponding to the predetermined light emission state (luminance gradation) is applied based on the voltage component (effect voltage Vdata) written during the write operation section Twrt, and the organic EL element OEL Emits light with a luminance gradation corresponding to the display data (gradation signal).

In this way, according to the display driving device and the display pixel according to the present embodiment, during the pre-charge period, the voltage component corresponding to the threshold voltage Vth13 is maintained between the gate and the source of the thin film transistor Tr13. Also, in order to maintain the voltage component Vdata corresponding to the current value between the gate and the source of the thin film transistor Tr13, the current value corresponding to the light emission state (gradation luminance) of the organic EL element OEL during the writing operation period. The gradation current Idata (write current Iwrt), which determines the condition of, is forced to flow between the drain and the source of the thin film transistor Tr13. As a result, the current gradation regulation mode which emits light with a predetermined luminance gradation by controlling the driving current Iem to flow in the organic EL element OEL based on a voltage component substantially corresponding to the gradation current Idata. The drive control method of is applied. Further, a function of converting the current level of the gradation current Idata corresponding to the required display data (luminance gradation) into a voltage level by a single switching element (thin film transistor Tr13) for driving, and a predetermined current value The function of supplying the driving current Iem having to the organic EL element OEL is implemented. This makes it possible to realize the light emission characteristics required regardless of the variation caused by the intrinsic element characteristics of the thin film transistors constituting the driving circuit DC and the change due to time.

In addition, in the display driving apparatus and the display pixel according to the present embodiment, the pre-charging operation is performed before the writing operation of writing the display data (gradation signal) to the display pixel PX and the light emitting operation of the organic EL element OEL. do. As a result, the gate terminal of the driving thin film transistor Tr13 provided on the driving circuit DC to maintain the voltage component corresponding to the intrinsic threshold voltage Vth13 of the thin film transistor Tr13 (charge is accumulated) and It is possible to set it in a state such that the pre-charge voltage Vpre is applied to the capacitor Cs connected between the source terminals.

As a result, even on each display pixel PX (drive circuit DC), the threshold voltage Vth13 of the provided switching element (thin film transistor Tr13) is changed due to a change in time or the driving history. Even if it is changed (moved) due to this, in the pre-charge operation, it is possible to set the state in which charge corresponding to the intrinsic threshold voltage Vth13 of each thin film transistor Tr13 can be properly accumulated. As a result, in the display data writing operation, it is not necessary to charge the capacitor Cs having the gradation current Idata based on the display data to the capacitance corresponding to the threshold voltage Vth13. The capacitor Cs can be charged by adding only the voltage component (effect voltage) Vdata corresponding to the display data (luminance gradation). Thus, the charge based on the display data can be rapidly accumulated in the capacitor Cs, to prevent the lack of writing occurrence, and to enable the organic EL element OEL to perform light emission of appropriate luminance gradation corresponding to the display.

In the present embodiment, in the threshold voltage detection operation performed before the display driving operation, the driving circuit DC of each display pixel PX (source side of the thin film transistor Tr13) is applied during the voltage application period Tpv. The configuration and driving control method of the display driving apparatus in which the detected detection voltage Vpv is applied to the data line DL from the compensation voltage DAC 150 through the input selection switch 182 and the write-side switch 183 are illustrated. do. However, the present invention is not limited thereto. For example, as shown in the following description, a dedicated power supply for applying the detection voltage Vpv to the data line DL may be provided.

11 is a structural diagram of an essential part showing another structural example of the display driving apparatus according to the present embodiment. Description of the same configuration as the above-described embodiment is omitted.

As shown in FIG. 11, the display driving apparatus according to the present structural example includes a voltage driving detection 190 for outputting voltage detection (Vpv), independently of the compensation voltage (DAC 150). Can be included in addition to. In addition, the display driving apparatus includes an input selection switch 182 provided on the data line input / output switching unit 180 such that the compensation voltage (DAC 150, pre-charge voltage Vpre), gray level signal generating unit 130, One of the gradation current Idata and the voltage power source detection 190 and the detection voltage Vpre is selectively connected to the data line DL.

In this configuration, only the input selection switch 182 of the data line input / output switching unit 180 and the write side switch 183 control the detection voltage Vpv through the data line DL to detect the voltage power supply 190. ), Thereby allowing load processing for the output operation of the detection voltage Vpv at the compensation voltage DAC 150 to be reduced.

(Display device operation: non-light-emitting operation)

Next, with reference to the drawings, the drive control method for the case of the non-light emitting operation in which the light emitting element does not emit light in the display driving apparatus and drive pixel having the above-described configuration will be described.

12 is a timing chart showing a drive control method (non-light emitting operation) of the display driving apparatus according to the present embodiment. 13 is a conceptual diagram showing another example of the data writing operation of the display driving apparatus according to the present embodiment. 14 is a conceptual diagram illustrating a non-light emitting operation of the display driving apparatus according to the present embodiment. Here, the description of the same drive control as the gradation luminance operation will be summarized or omitted.

In the driving control operation of the display driving apparatus according to the present exemplary embodiment, as illustrated in FIG. 12, the driving thin film transistor Tr13 provided on each display pixel PX is used to compensate for the threshold voltage Vth13. The display driving operation for maintaining the voltage component corresponding to the threshold voltage Vth13 and the gradation signal (non-emitting display voltage) corresponding to the display data for setting the organic EL element OEL to the non-emitting state in a subsequent operation. (Vzero)) may be included.

That is, during the driving control operation at the time of performing the gradation display operation described above, the power supply voltage Vsc at the time of moving from the writing operation section Twrt set at the display driving operation (display driving section) to the light emitting operation section Tem. ) Is set to move from the low potential Vs to the high potential Ve. For this reason, the phenomenon that the potential (gate potential) applied to the gate terminal (contact point N11) of the thin film transistor Tr13 rises due to a change in the charge held in the parasitic capacitance component on the thin film transistor Tr11. appear.

Here, when the luminance gradation based on the display data is set to the minimum gradation (black display state), the current value of the gradation current Idata is set to the minimum state or 0 (that is, the state in which the gradation current Idata does not flow). . However, the voltage (both terminal side potential Vc) charged in the capacitor Cs during the pre-charge period Tth is set to a value close to the threshold voltage Vth13 inherent to the thin film transistor Tr13. Therefore, when a slight change in the gate potential occurs due to the movement from the writing operation section Twrt to the light emitting operation section Tem, the thin film transistor Tr13 is turned on, so that the non-light emitting operation ( Black display) may not be implemented (unstable).

In order to stabilize the non-luminous display operation, the voltage component (accumulated charge) applied to the capacitor Cs is discharged during the light emitting period, and the voltage Vgs between the gate and the source of the thin film transistor Tr13 (capacitor Cs) is discharged. It is preferable that both terminal side potentials (Vc) of be set to a level sufficiently lower than the threshold voltage Vth13 of the thin film transistor Tr13. It is more preferable that the voltage Vgs is set to 0 V (that is, both contact points N11 and N12 have the same potential).

In order to implement such a voltage state, a write operation is performed using the gradation current Idata having the above-described minimum current value. In this case, it takes a relatively long time to discharge the charge accumulated in the capacitor Cs to set the voltage Vgs between the gate and the source to the required charge capacity (voltage value). In particular, as the voltage component (both terminal potentials Vc) applied to the capacitor Cs during the write operation Twrt of the previous display driving section (one processing cycle section, Tcyc) approaches the maximum luminance gradation voltage. The charge capacity accumulated in the capacitor Cs becomes large. As a result, it takes longer to discharge the charge to set the voltage to the required voltage value.

Therefore, as shown in Fig. 1, in the display driving apparatus according to the present embodiment, the gradation signal generation unit 130: the organic EL element (OEL, optical element) emits light at a predetermined luminance gradation corresponding to the display data. Means for generating and supplying a gradation current (Idata) to perform the operation; The non-luminescing display voltage Vzero is applied to the data line DL at the lowest gradation luminance (black display state), and the non-luminescing operation (black display is performed without performing the light emitting operation of the organic EL element OEL. Means for generating and supplying a non-luminous display voltage Vzero to

Incidentally, in this embodiment, the non-light emitting display voltage Vzero is driven by the gray scale signal generating unit 130 through the data line DL, the source terminal of the driving circuit DC, the thin film transistor Tr13, the contact point ( N12)) is presented. However, the present invention is not limited thereto. For example, a dedicated power supply may be provided for supplying the non-luminous display voltage Vzero to the data line DL.

As shown in Fig. 12, during the display driving operation after the end of the above-described threshold voltage detection operation, the driving control method in the display driving apparatus having such a configuration is: a predetermined display driving period (one processing cycle period, Tcyc). The pre-charge voltage Vpre is applied to the display pixel PX within the driving thin film transistor between the gate and the source (both ends of the capacitor Cs) of the thin film transistor Tr13 provided on the driving circuit DC. A pre-charge section Tth that maintains the voltage component corresponding to the intrinsic threshold voltage Vth13 of Tr13 (so that the capacitor Cs accumulates or discharges charge); The gray level signal (non-emission voltage Vzero) corresponding to the display data is applied to each display pixel PX (driving circuit DC) through the data line DL, and between the gate and the source of the thin film transistor Tr13. A write operation period Twrt for discharging the charge held between the gate and the source (in the capacitor Cs) of the thin film transistor Tr13 to set the voltage Vgs to 0 V; And a light emitting operation section Tem for preventing the organic EL element OEL from performing a light emitting operation (non-light emitting operation); (Tcyc? Tth + Twrt + Tem).

The voltage corresponding to the intrinsic threshold voltage Vth13 of the driving thin film transistor Tr13 during the pre-charging operation before the writing operation section Twrt in the same manner as the driving control operation at the time of performing the above-described gray scale display operation. The component is held (charge accumulates) between the gate and the source (capacitor Cs) of the thin film transistor Tr13, and then, in the sequential operation, as shown in Fig. 13, during the writing operation of the gradation signal, for example, A non-luminous display voltage Vzero having a potential equal to a low-potential power supply voltage Vsc = Vs is obtained from the display driver 100 to the data line input / output switching unit 180 and the data line DL. Directly applied to the source terminal (contact point N12) side of the thin film transistor Tr13 provided on the display pixel PX (driving circuit DC) through the gate and the source (both ends of the capacitor Cs). Transfer between potentials (Vc) It shall be set (Vgs) to the 0 V.

In this way, substantially all the charge accumulated in the capacitor Cs is discharged, and the voltage Vgs between the gate and the source of the thin film transistor Tr13 is sufficiently lower than the intrinsic threshold voltage Vth13 of the thin film transistor Tr13. Set the voltage value (about 0 V). As a result, even if the power supply voltage Vsc changes from the low potential Vs to the high potential Ve at the time of moving from the write operation period Twrt to the light emission operation period Tem, the thin film transistor Tr13 The gate potential (potential of the contact point N11) rises slightly, and as shown in Fig. 14, the transistor Tr13 is not turned on (the off state is maintained), and no driving current Iem is induced in the organic EL. It is not applied to the element OEL, and no light emitting operation is performed (a non-light emitting state is provided).

As a result, at the time of non-light emitting operation, in order to substantially discharge all the charge accumulated in the capacitor Cs connected between the gate and the source of the driving thin film transistor Tr13, the gradation current corresponding to the non-light emitting display data is added. Compared with the case where it is applied via the data line DL, the non-light emitting state (non-light emitting display operation) of the organic EL element OEL is advantageously reduced while reducing the time required for writing operation of the non-light emitting display data. It is possible to implement Therefore, in addition to the display driving operation for performing the general gray level signal, the display driving operation for performing the non-luminous display is switched and controlled in accordance with the display data (luminance gradation data), and as a result, For example, a light emission operation having 256 gray levels can implement a relatively high luminance.

As shown in FIG. 1, in the display pixel PX according to the present embodiment, an n-channel amorphous silicon thin film transistor is applied to the case where the thin film transistors Tr11 to Tr13 are provided on the driving circuit DC. The configuration shown is shown. In addition, the p-channel amorphous silicon thin film transistor can be applied to all thin film transistors Tr11 to Tr13.

Here, when the p-channel thin film transistor is applied, the signal is set in such a manner that the high-low of the on-level and off-level are reversed.

In addition, as shown in FIG. 1, in this embodiment, a circuit configuration in which three thin film transistors Tr11 to Tr13 are provided as the driving circuit DC provided on each display pixel PX will be described. do. However, the present invention is not limited thereto. In order to accumulate the voltage component of the capacitor between the gate and the source of the transistor or connected to the parasitic capacitance, a single thin film transistor is used to correspond to the display data and to convert the supplied gradation current into a voltage component and accumulated It is apparent that other circuit configurations may also be provided that satisfy the conditions for implementing the driving function for controlling the driving current supplied to the organic EL element OEL (optical element) based on the voltage component.

Also, in the driving control method of the display driving device and the display pixel, as a pre-charging operation, the pre-charging voltage Vpre having a voltage value based on the threshold compensation is applied to the data line DL from the compensation voltage DAC 150. The case where it is applied to each display pixel PX is described. However, the present invention is not limited thereto. For simplicity, the voltage component (driving transistor Tr13) is used to compensate for the threshold voltage of the current Ids between the gate and the source of each driving transistor Tr13 provided on the driving circuit DC of each display pixel PX. Apparatuses and methods that can maintain the intrinsic threshold voltage Vth13) are both applicable.

For example, a configuration may be provided in which a pre-charge current having a current value based on threshold compensation data is applied from the display driver 100 to each display pixel PX through the data line DL.

<Display device>

Next, a display driving apparatus and a driving control method according to the present invention will be described with reference to the drawings.

Fig. 15 is a schematic block diagram showing an example of the overall configuration of a display apparatus according to the present invention, and Fig. 16 is an example of a display panel applied to the display apparatus and the accessory circuit (selection driver, power supply driver) according to this embodiment. It is a schematic structural diagram which shows. Here, the same components as those of the display driving apparatus and display pixel (drive circuit) described above in this embodiment will be described with the same or the same reference symbols with reference to the drawings.

As shown in Figs. 15 and 16, the display apparatus 200 according to the present embodiment: includes a drive circuit DC each having the same circuit configuration as the above-described embodiment, and has a matrix of n rows * m columns. An organic EL element proximate to each intersection of a plurality of display pixels arranged in a type (n, m is an arbitrary integer), and a plurality of selection lines SL arranged in rows and a plurality of data lines DL arranged in columns A display panel 210 including an OEL (optical element), connected to a selection line SL of the display panel 210, and applying a selection signal Ssel to each selection line SL at a predetermined time. A selection driver (selection driving unit 220) sequentially applied to the power supply voltage line (VL) arranged in parallel to each selection line (SL), and to each power supply voltage line (VL) at a predetermined time; Sequentially apply the power supply voltage Vsc on a predetermined voltage level. A power driving unit (power driving unit 230) connected to the data line DL of the display panel 210, and during the display driving period Tcyc, a preset voltage corresponding to the intrinsic threshold voltage of the switching element of the display pixel PX. The display pixels PX and the driving circuit DC of each column during the above-described threshold voltage detection period Tdec while applying the charging voltage Vpre to each display pixel PX of each column through each data line DL. The threshold voltage is detected through each data line DL at a time point related to the switching element (thin film transistor) for the driving unit provided on the sigma, and then a gradation signal corresponding to each display data (gradation current Idata or A data driver (data driver unit 240) for supplying a non-luminous display voltage Vzero; when supplied from a selection control signal, a power supply control signal and a display generating circuit 260 to be described below. On the basis of at least a selection signal driving unit 220, a power driver 230, and a system controller 250 for generating and outputting a data control signal for controlling the operation of the data driver 240; The data driver 240 extracts or generates a timing signal (such as a system clock) for displaying predetermined image information based on the display data on the display panel 210 to supply a timing signal to the system controller 250. And a display generation circuit 260 for generating display data (luminance gradation data) including a digital signal based on an image signal supplied from the outside of the display apparatus 200 to supply data to the display device 200.

There will be a clear description of each configuration below.

(Display panel)

In the same manner as in the display pixels shown in the above-described embodiment (see FIG. 1), as shown in FIG. 6, each display pixel PX disposed in the display panel 210 is: from the selection driver 220. The driving current Iem corresponding to the display data based on the selection signal Ssel applied through the selection line SL, and the power supply voltage Vsc applied from the power driver 230 through the power supply voltage line VL. And a driving circuit DC for generating a gradation signal (gradation current Idata or non-emitting display voltage Vzero) applied from the data driver 240 through the data line DL; And an organic EL element OEL (optical element) for performing the light emitting operation with a predetermined luminance gradation corresponding to the current value of the driving current Iem supplied from the driving circuit DC. In this embodiment, the organic EL element OEL is applied as an optical element as in the above-described embodiment (see Fig. 1). Other current controlled optical elements capable of performing light emitting operations with a predetermined luminance gradation corresponding to the current value of the drive current Iem can also be applied.

(Selective drive section)

The selection driver 220 selects the display pixels PX of each row in a selection state for supplying an on-level selection signal Ssel to each selection line SL based on the selection control signal supplied from the system controller 250. Set it. In particular, the display pixels PX in each row are set sequentially. The selection signal Ssel is applied to the selection line SL of the row while the threshold voltage detection operation and the display driving operation (pre-charging operation and writing operation) except the light emitting operation are performed on the display pixels PX of each row. By sequentially applying the operation to each row at a predetermined timing, the display pixels PX of each row are sequentially set to the selected state.

Here, for example, as shown in FIG. 16, the selection driver 220 includes: a movement signal corresponding to the selection line SL of each row based on the selection clock signal SCK and the system controller 250 to be described below. A known shift register 221 for sequentially outputting the selection start signal SST supplied as a selection control signal from the controller; The shift signal output from the shift register 221 is converted into a predetermined signal level, and the signal is selected as the selection signal Ssel based on the output control signal SQE supplied as the selection control signal from the system controller 250. And an output circuit unit (output buffer 222) for outputting to each selection line SL.

(Power drive)

The power driver 230 supplies a high-potential power supply voltage (Vsc = Ve) to the display pixels PX of each row during the emission period based on the power control signal supplied from the system controller 250. The low-potential power supply voltage (Vsc = Vs) is applied to the power supply voltage line (VL) and the operation section (threshold threshold detection section (Tdec), pre-charge section (Tth), and display) excluding the light emission operation section. Is applied to the power supply voltage line VL in the row during the write operation section Twrt in the driving section Tcyc.

Here, as shown in FIG. 16, in the same manner as the selection driver 220, the power driver 230 may include: a movement signal corresponding to the selection line SL of each row based on the selection clock signal VCK and the following description. A known shift register 231 for sequentially outputting the selection start signal VST supplied as a power control signal from the system control unit 250 to be operated; The shift signal from the shift register 221 is converted into predetermined signal levels (voltage values Ve and Vs), and the shift signal is supplied to the power supply voltage Vsc based on the output control signal VQE supplied as the power supply control signal. And an output circuit unit (output buffer) 232 for outputting to each power supply voltage line VL.

(Data Drive)

The data driver 240 is operated in the same manner as the display driver 100 shown in this embodiment described above: the shift register / data register unit 110, the display data latch unit 120, and the gray scale shown in FIG. The signal generation unit 130, the detection voltage (ADC) 140, the compensation voltage (DAC 150), the frame memory 170, and the data line input / output switching unit 180 may be included.

In Fig. 1 a configuration corresponding to a single display pixel PX is shown. In the data driver 240 corresponding to the present embodiment, the data line input / output switching unit 180 is provided for each data line DL provided in the column direction on the display panel 210. As a result, the voltage detecting side constituting the data line input / output switching unit 180 based on the detection voltage Vpv, the pre-charge voltage Vpre and the gradation signal (gradation current Idata, or the above-described driving control method). An operation or detection voltage (sequential or sequential) of applying one of the non-light-emitting display voltages Vzero to each row by the switch 181, the input selection switch 182, and the write-side switch 183. Any one of the operations for measuring Vpv) is performed sequentially for the display pixels PX of each row.

That is, the shift register / data register unit 110 provided on the data driver (display driver unit) corresponding to this embodiment is a data control signal (shift clock signal and sampling start signal) supplied from the system controller 250. A display supplied from the display signal generation circuit 260 based on the output timing of the moving signal generated corresponding to one row portion (or data line DL of each column) of the display pixel PX of each column on the basis of Load one row portion of data sequentially.

In the display data latch unit 120, one row portion of the display data loaded from the shift register / data register unit 110 is transmitted based on the data control signal (data latch signal), and the display data is displayed for each display in each column. Retained for pixel PX.

Based on each display data held in the display data latch unit 120, the gradation signal generation unit 130 generates a non-light-emitting voltage Vzero having a gradation current Idata or a predetermined voltage value corresponding to the display data. And the current or voltage is applied in parallel simultaneously or sequentially as a gradation signal.

In particular, in the case where the display data is gradation display data for a predetermined general gradation signal parallel to the light emitting operation of the organic EL element OEL, for example, the voltage is an analog voltage having a predetermined voltage value based on the gradation reference voltage. Conversion (digital to analog conversion). In addition, a gradation current Idata having a current value corresponding to the display data is generated (voltage-current change processing), and output to the data lines DL of each column at a predetermined timing. On the other hand, when the display data is non-light emitting display data which is not in parallel with the light emitting operation of the organic EL element OEL (optical element), the predetermined non-light emitting display voltage Vzero is a column of data lines DL at a predetermined timing. )

As described in the driving control method (non-light emitting display operation), a switching element (thin film transistor Tr13) for the driving portion provided on the driving circuit DC constituting the display pixel PX by the pre-charging operation. By discharging the charge accumulated between the gate and the source (in the capacitor Cs) of the non-luminescent display to any voltage value (or about 0 V) required to set the voltage Vgs between the gate and the source. The voltage Vzero is set. Here, the non-luminous display voltage Vzero and the gradation reference voltage for generating the gradation current Idata are supplied, for example, from a power supply circuit or the like (not shown).

The detection voltage ADC 140 detects the threshold voltage of the switching element (thin film transistor Tr13) for the driver provided through each data line DL on the display pixels PX of each row in the column set in the selected state. At the time of performing the operation, the threshold voltage (or a voltage component corresponding to the threshold voltage) is measured simultaneously or in parallel with the detection voltage Vdec and the image information in the display panel 210 is measured. Prior to the display operation (display driving operation of the display pixel PX), during the threshold voltage detection operation, the threshold data is latched to the threshold data latch unit 160 by converting the threshold voltage into threshold voltage detection data including the digital signal voltage. Outputs

The compensation voltage DAC 150 performs a display operation (display pixel PX) of image information in the display panel 210 simultaneously or sequentially with a predetermined detection voltage Vpv through each data line DL. Display driving operation) is output to the display pixel PX of each column of one row set (a switching element for the driving unit provided on the driving circuit DC) in the selected state of the threshold voltage detection operation.

In addition, the compensation voltage DAC 150 is a pre-charge voltage based on the compensation threshold compensation data for the intrinsic threshold voltage of the switching element provided on the display pixel PX of each column in the set of one row in the selected state. (Vpre) and the pre-charge voltage (Vpre) of each column through each data line (DL) during the display operation (display drive operation of the display pixel (PX)) of the image information in the display panel 210 Parallel to the display pixel PX and output simultaneously or sequentially.

The threshold data latch unit 160 displays each column in one row set in a selected state in the threshold voltage detection operation before the display operation of the image information in the display panel 210 (display drive operation of the display pixel PX). The shift register / data register unit 110 is sequentially transferred to the frame memory 170 in a sequential step, which is converted by the detection voltage ADC 140 for the pixel PX and retrieves and maintains the generated threshold detection data. Retrieve a row portion of the threshold detection data sent to.

In addition, the threshold data latch unit 160 loads and maintains threshold compensation data corresponding to the threshold detection data for each display pixel PX in each column in the set of one row in the selected state, and stores the threshold compensation data in each of the rows. The threshold compensation data is transmitted to the column compensation voltage DAC 150, and the threshold compensation data is transferred to the shift register / data register unit 110 during the display operation of the image information in the display panel 210 (the display driving operation of the display pixel PX). By the frame memory 170 in order.

(System control unit)

The compensation voltage DAC 150 controls selection of the driving unit 220, the power driving unit 230, and the data driving unit 240 in order to operate the respective driving units at a predetermined timing. A signal, a power control signal, and a data control signal are generated and output. As a result, a selection signal Ssel having a predetermined voltage level, a power supply voltage Vsc, and a gradation signal (gradation current Idata or non-luminous voltage Vzero) are generated and outputted, so that each display pixel ( PX, the drive circuit (DC) to perform the threshold voltage detection operation (voltage application operation, voltage convergence operation and voltage read operation) and the display drive operation (pre-charge operation, write operation and light emission operation) to perform the display Control of the display of predetermined image information based on the image signal on the panel 210 is performed.

(Display signal generation circuit)

The display signal generating circuit 260 extracts, for example, the luminance gray level signal component from the image signal supplied from the outside of the display apparatus 200, and displays the luminance gray level signal component for each row of the display panel 210. FIG. The display data (luminance gradation data) is supplied to the shift register / data register unit of the data driver 240. Here, when the video signal includes a timing signal for adjusting the display timing of video information, such as a television broadcast signal (composite video signal), the display signal generation circuit 260 is in addition to the function of extracting the luminance gradation signal component. The timing signal component may be extracted, and the component may be supplied to the system controller 250. In this case, the system controller 250 generates control signals supplied to the selection driver 220, the power driver 230, and the data driver 240 based on the timing signal supplied from the display signal generator 260. do.

Incidentally, in the display device according to the present embodiment, the selection driver 220 connected to the selection line SL and the power driver 230 connected to the power supply voltage line VL are separately around the display panel 210. Show the configuration provided. However, as described in the above drive control method (see FIGS. 7 and 12) of the display driving apparatus (corresponding to the data driver 240), it is applied to the selection line SL (from the selection driver 220). The selected selection signal Ssel and the power supply voltage Vsc applied to the power supply voltage line VL (from the power driver 230) are inversely related to each other for the display pixels PX of the individual rows. It is set to a state having. As a result, when each display pixel PX disposed on the display panel 210 performs a display driving operation (especially a light emitting operation) independently of the row unit (especially, the driving control method of the display apparatus to be described below). In the case of the example of 1), in the configuration without the power supply driver 230, the signal level of the selection signal Ssel generated by the selection driver 220 is reversed (level reversal processing), and the signal level is converted so that a specific row is obtained. In order to apply a level of a signal to the power supply voltage line VL, a configuration may be applied so as to have a predetermined voltage level.

<Display driving control method of display device>

Next, a drive control method (display drive action) of the display device according to the present embodiment will be described.

The timing of performing a series of threshold voltage detection operations is controlled based on the individual control signal output from the system controller 250.

First, the first to third display drive control methods of the display apparatus, which are controlled such that the threshold voltage detection driving can be performed before the display driving operation, for example, at an arbitrary timing, for example, at the start time or the rest time of the system (display device). The fourth embodiment and modifications will be described.

(First example)

17 is a timing chart showing a first example of a display driving method of the display device according to the present embodiment.

Here, the description will be omitted for the driving control method (see FIGS. 2 and 7) such as the display driving apparatus and display pixel (drive circuit) of the above-described embodiment.

 Incidentally, for the sake of explanation, the present embodiment will be provided with a configuration in which display pixels of twelve rows (first row to twelfth row) are arranged.

As shown in FIG. 17, in the first example of the drive control operation of the display apparatus 200 according to the present embodiment, the display operation of the image information in the display panel 210 (display drive operation of the display pixel PX). Previously, the threshold voltage detection operation (threshold voltage detection section Tdec) is a driving circuit DC disposed on each display pixel PX with respect to all the display pixels PX disposed on the display panel 210. In order to control the light emission state of the organic EL elements (OEL, optical elements), detection of a threshold voltage (or a voltage component corresponding to the threshold voltage) of the driving switching element (thin film transistor) is performed first. Thereafter, voltage compensation corresponding to the threshold voltage of the switching element is maintained (threshold threshold voltage is accumulated) in the display pixels PX of each row of the display panel 210 within the frame period Trf (about 16.7 msec), and then sequentially In a step, a gradation signal (gradation current Idata or non-emitting display voltage) for each display pixel PX is written.

Here, in the timing chart shown in FIG. 17, the shaded portion of each row of the threshold voltage detection section Tdec shown by hatching indicates a series of threshold voltage detection operations presented in this embodiment. Each operation may include a voltage application operation, a voltage convergence operation, and a voltage read operation. The threshold voltage detection operation is performed sequentially by shifting the timing in such a way that the threshold voltage detection does not overlap each other for each row in time.

In addition, with respect to the display driving operation (display driving section Tcyc), in the same manner as in the above-described embodiment, a series of driving control displays for each row of the display panel 210 during one frame section tfr. The pixels PX and the driving circuits DC are sequentially performed at predetermined timings for each row. The drive control may include a pre-charging operation, a writing operation, and a light emitting operation. The pre-charge operation (pre-charge interval) is detected by the threshold voltage detection operation for each display pixel PX (switching element for the driver), and based on the stored threshold detection data (threshold compensation data), each display Write a pre-charge voltage to compensate for the threshold voltage of the pixel PX. The write operation (write operation section Twrt) writes the gradation signal (non-light-emitting voltage charging section Tth corresponding to the gradation current Idata or display data). The light emission operation (light emission operation section Tem) causes each display pixel PX (organic EL element OEL) to emit light with a luminance gradation corresponding to the display data at a predetermined timing.

Here, in the timing chart shown in FIG. 17, the shaded portions (marked with Tth + Twrt) of each row of the display driving section Tcyc shown by the reticle lines indicate the pre-charging operation and the writing operation of the above-described embodiment. . In particular, in an embodiment, the pre-charge operation and the write operation for each row are performed sequentially with time shifts, so that the pre-charge operation and the write operation for each row do not overlap each other. Accordingly, the light emitting operation is performed in the order of starting with the display pixels PX of the row where the writing operation is completed. That is, only the light emitting operation of the display operation for each row is performed by the shading part, so that only the light emitting operation is overlapped (partially parallel) in time between each row.

Hereinafter, the first example of the display driving operation according to the embodiment will be further described in detail.

As shown in Fig. 17, the display pixels in the i-th row in the pre-charge section Tth and the write operation section Twrt (shown as cross hairs in the figure) of the display driving operation (display driving section Tcyc). As shown in Figs. 7 and 12 showing the result that PX is selectively set in the selected state, the ON level (high-level) selection signal Ssel is specified from the selection driver 220 to the display panel 210. Is applied to the selection line SL in a row (e.g., i-th row; 1 ≦ i ≦ 12). In addition, in the pre-charge section Tth and the write operation section Twrt, the low-potential power supply voltage Vsc = Vs is applied from the power driver 230 to the power supply line VL in the i-th row. .

Then, at this point of synchronization (for convenience, referred to as " selection timing "), an individual pre-charge that compensates the threshold voltage of the switching element (thin film transistor) provided in each display pixel PX (driving circuit DC). The voltage Vpre is applied to each data line DL from the compensation voltage DAC 150 provided in the data driver 240 in the pre-charge section Tth. As a result, the voltage component corresponding to the intrinsic threshold voltage of the switching element (thin film transistor Tr13) is equal to the control terminal (especially the gate of the thin film transistor Tr13) of the switching element of each display pixel PX in the i-th row. Between the source terminals; both ends of the capacitor Sc) (charges accumulate).

Then, in synchronization with the selection timing, the gradation signal corresponding to the display data of each display pixel PX (gradation current Idata, or non-emitting display voltage Vzero) is transferred to the data driver in the write operation section Twrt. The gray level signal generating unit 130 provided at 240 is applied to the data lines DL of each column. As a result, the voltage component corresponding to the gradation signal (display data) is determined by the control terminal of the switching element of the display pixel PX of each column in the i-th row (particularly, between the gate and the source terminal of the thin film transistor Tr13; ) At both ends) (charge is charged or discharged).

Here, the display data supplied from the display generating circuit 260 to the data driving unit 240 in the same manner as the above-described drive control method, the gradation accompanying the light emitting operation of the organic EL element (optical element) OEL. In the case of display data (gradation value excluding 0 bit; gradation display operation), the gradation current Idata corresponding to the display data is supplied to the data driver 240 (gradation signal generation) supplied to the display pixels PX of the corresponding column. Generated by the unit 130. On the other hand, when the display data is non-light emitting display data (gradation signal is 0 bits; non-light emitting operation) not accompanied by the light emitting operation of the organic EL element (optical element) OEL, the predetermined non- The light emitting display voltage Vzero is generated by the data driver 240 supplied to the display pixels PX of the corresponding columns.

Therefore, with respect to the display pixel PX supplied as the gradation current Idata, the voltage component (effect voltage Vdata) based on the gradation current Idata is row (between the gate and the source of the driving thin film transistor). Is charged by adding to a voltage component corresponding to the threshold voltage Vth13 charged to each display pixel PX by a pre-charge operation.

Further, in the display pixels supplied with the non-luminous display voltage Vzero as the gray level signal, the voltage component (charge) corresponding to the threshold voltage Vth13 charged to each display pixel PX in a row corresponds to the display data. The voltage (0 V) is completely discharged as a result of being set in the switching element to drive (between the gate and the source of the thin film transistor).

Next, as shown in FIG. 17, in the light emission operation section Tem (marked with a shaded portion in the drawing) of the display driving operation (display driving Tcyc), the OFF level (low level) selection signal Ssel is As shown in FIGS. 7 and 12, the selection driver 220 is applied to the selection line SL in the i-th row, whereby each display pixel PX in the i-th row is set to the non-selection state. . In addition, the application of the gradation signal from the gradation signal generation unit 130 included in the data driver 240 to each data line DL is blocked.

In synchronization of this timing, a high-potential power supply (Vsc = Ve) is applied from the power supply 230 to the power supply voltage line VL in the i-th row. As a result, the driving current Iem corresponding to the display data (gradation signal) is supplied to the organic EL element OEL based on the voltage component charged in the display pixel PX in the i-th row, whereby a predetermined luminance is obtained. A light emission operation or a non-light emission operation with a gradation is performed.

Here, when the gradation signal written to each display pixel PX is based on the gradation display data (gradation value except 0 bits) accompanied by the light emission operation of the organic EL element OEL, the gradation current Idata The driving current Iem as described above is supplied to the organic EL element OEL, and the organic EL element OEL executes a light emission operation (gradation display operation) having a predetermined luminance gradation corresponding to the display data. On the other hand, when the gradation signal is based on non-luminescence display data (gradation signal is 0 bits; non-luminescence operation) which is not accompanied by the light emission operation of the organic EL element (optical element) OEL, the driving current Iem ) Is not supplied to the organic EL element OEL so that the light emitting operation is not performed (non-light emitting display operation; black display operation).

In such an i-th row, the light emitting operation (or non-light emitting operation) with respect to the display pixel PX is started in synchronization with the end timing (immediately after timing) of the pre-charging operation and the writing operation, and the light emitting operation is Pre-charging and writing operations, for example, are executed successively with respect to the i-th row until the start timing (immediately before start) of one frame section Tfr.

Further, in synchronization of the end timing (immediately after timing) of the pre-charge and write operation with respect to the display pixel PX in the i-th row, the same pre-charge operation and the write operation as described above are close to (i + 1). Start with respect to the display pixel PX in the) -th row, so that the light emission operation for the (i + 1) -th row is started in synchronization with the end timing (immediately after timing) of the pre-charge operation and the write operation. .

As a result, as shown in Fig. 17, the operation of charging each display pixel PX with a suitable voltage component corresponding to the display data (gradation signal) by the pre-charge operation and the write operation is performed in one frame period ( In Tfr, each row of the display panel 210 is sequentially executed by the timing shift with respect to the display pixel PX (drive circuit DC) so that the rows do not overlap each other. On the other hand, in the row where the pre-charging operation and the writing operation are completed, the light emitting operation (or non-light emitting operation) is partially overlapped with each other in time between the rows having a predetermined luminance gray scale in order from the display pixel PX. The drive control operation in which) is executed is realized.

In this manner, according to the display device of the present embodiment and the drive control method thereof, display pixels and display devices corresponding to the drive control method of the general gray scale definition mode are provided in the configuration applied to the data driver and the display panel. As a result, in the normal gradation display operation (except for the time point of the non-light emitting operation), the driving current supplied to the optical element (organic EL element) can be controlled based on the current value of the gradation current corresponding to the display data. . In addition, the current level of the gradation current is switched to the voltage level by a single switching element (driving thin film transistor) provided in each display pixel, and the current value of the driving current can be set based on the voltage level. As a result, it is possible to stably realize a desired light emission characteristic for a long time without changing the device characteristic (threshold voltage) of the switching element (thin film transistor) provided and driven by each display pixel (driving circuit), which changes over time. Makes it possible.

Further, with respect to the display device according to the present embodiment and the drive control method, display pixels (drive circuits) before writing operation of display data (gradation signal) to each display pixel and light emitting operation of the optical element (organic EL element). The threshold voltage of the switching element (driving thin film transistor) provided with () is the pre-charge corresponding to the threshold voltage detected in the switching element provided with the display pixel (drive circuit) immediately before the display data write operation is performed on each display pixel. A voltage is applied to preferentially detect and store all display pixels arranged on the next display panel (threshold voltage detection operation). As a result, the voltage component (charge) corresponding to the intrinsic threshold voltage of the switching element is maintained at the control terminal (between the gate and the source of the driving thin film transistor) of the switching element provided with each display pixel (varied by Vth shift). It is possible to set the threshold voltage separately). Thus, in the writing operation of the display data, the voltage component can be charged by adding only the voltage component corresponding to the display data, so that the voltage component based on the display data can be written quickly and appropriately.

Therefore, in the drive control method of the current gradation regulation mode, the voltage component corresponding to the display data can be quickly and suitably written even at the time of the light emission operation with the low luminance gradation corresponding to the display data. . Therefore, the occurrence of write insufficiency in each display pixel can be suppressed, and the influence of Vth shift of the switching element (driving thin film transistor) provided in each display pixel can be eliminated. As a result, the desired image information can be preferably displayed for a long time with a suitable gradation gradation corresponding to the image signal.

Also, at the time of non-luminescent display, a predetermined non-luminescent display voltage (0 bit grayscale value) corresponding to the display data is supplied to each display pixel to drive (between the gate and source of the thin film transistor) the switching element. All held voltage components can be charged quickly. As a result, the supply of the drive current to the optical element (organic EL element) can be safely cut off, and the non-light emitting display operation can be stably realized.

Further, according to the display device according to the present embodiment and the drive control method, the next pre-charge section and the write operation section of each frame section of the display panel except the pre-charge section and the write operation section of each frame section The apparatus is driven and controlled so that the light emission operation continues up to the start point. As a result, the light emission time of each display pixel (optical element) can be set for a long time, and the image information can be displayed with high light emission luminance. In other words, this means that the image information can be displayed with sufficient luminance even when the emission luminance of each display pixel is reduced. Thus, the power consumption associated with the display of the image information can be reduced.

(Second example)

Next, with reference to the drawings, a second example of the drive control method applicable to the display device according to the present embodiment will be described.

18 is a timing chart showing a second example of the drive control method for the display device according to the present embodiment.

Here, the same drive control method as in the above-described first example (refer to Fig. 17) will be simplified. In addition, the shaded portions in the drawings show the same operating states as the above-described first embodiment.

19 is a block diagram of an essential part showing one example of the display apparatus for realizing the second example of the drive control method of the display apparatus according to the present embodiment.

Here, the same components of the display device described in the above-described embodiments will be described by adding the same reference numerals and symbols.

According to the embodiment, in the second example of the drive control operation of the display apparatus 200, each of the display panel 210 in one frame period Tfr (about 16.7 msec) in the same manner as in the first embodiment. Compensating the threshold voltage with respect to the display pixel PX (drive circuit DC) for each row, and thereafter, for each row, the threshold voltage detection operation is performed on all display pixels PX arranged in the display panel 210 at a predetermined timing. This is executed sequentially. Thereafter, the operation of writing the gradation signal (gradation current (Idata or non-emitting display voltage Vzero)) corresponding to the display data ("Tth + Twrt" in the drawing) is repeated sequentially for every row, and Display driving operation (display driving) in which a plurality of rows of display pixels PX (organic EL elements OEL), which are divided into groups in advance, execute light emitting operations simultaneously occurring with luminance gradations corresponding to display data (gradation signals) The section Tcyc) is executed to display image information on one screen unit of the display panel 210.

Here, in the second example of the display driving operation according to the present embodiment, in particular, all the display pixels PX arranged on the display panel are first divided into groups for a plurality of rows in advance. For example, as illustrated in FIG. 18, twelve rows of the display pixels PX constituting the display panel 210 may be adjacent to the first to fourth rows, adjacent to the fifth to eighth rows, In the ninth to twelfth rows, four rows of the display pixels PX are divided into one group set.

Then, in one frame period Tfr, the pre-charging operation and the writing operation are executed sequentially with respect to the display pixel PX (drive circuit DC) for each row of the display panel 210 with the shift of the timing. do. Next, in each group, the light emitting operation is performed on the group which finishes the writing operation on the display pixel PX in all rows included in the group.

For example, in a group in which the display pixels PX are in one group set in the first to fourth rows, the pre-charging operation and the writing operation are performed in order from the display pixels PX in the first row. At the time when the write operation is finished with respect to the display pixel PX in the fourth row, four rows in the group of display pixels PX emit light based on the display data (sequential signals) written to each display pixel PX. The operations are executed at the same time. This light emission operation continues continuously until the next pre-charge operation and the write operation are continued.

Further, at the time when the write operation is finished with respect to the display pixel PX in the fourth row, the pre-charge operation and the write operation are the group fifth in which the display pixels PX are set as one group in the fifth to eighth rows. The rows are executed in order from the display pixels PX. In the following, the same operation is repeatedly executed until the writing operation is terminated by the display pixel PX in the twelfth row of the next group.

In this manner, the display apparatus is driven and controlled in such a manner that the pre-charging operation and the writing operation are executed sequentially at predetermined timings for each row, so that the writing operation is performed on the display pixels PX in all the rows included in the group. At the time point when it is finished with respect to each preset group, the light emission operation is performed simultaneously for all the display pixels PX of the group. As a result, in the display driving operation according to the second example, all of the pre-charging operation and the writing operation are performed in the non-luminescing state (black display state) in the interval where the pre-charging operation and the writing operation are performed on the display pixels PX in another row of the same group. The display device is controlled in such a way that all display pixels in the group perform a non-luminescing operation so that the display pixels are set.

As shown in Figs. 7 and 12, for example, high-potential power is supplied to the power supply voltage line VL in all rows of the group after the pre-charging operation and the writing operation are finished in all the rows included in the group. The power driver at the time of the pre-charge operation and the write operation in the section in which the pre-charge operation and the write operation are performed on the display pixels PX in all rows included in the same group after applying the voltage Vsc = Ve. The display driving operation can be realized by controlling the display device in such a manner that the low-potential power supply voltage Vsc = Vs applied to the power supply voltage line VL of the row by 230 is continuously applied.

Further, for example, as shown in FIG. 19, the single power supply voltage line VL is connected to the first to fourth rows (or the fifth to eighth rows and the ninth to twelfth rows). Branched and commonly connected to the display pixel PX, a single power supply voltage Vsc is simultaneously applied to each group, and a single power applied from the power driver 230 to the display pixel in all rows included in the same group. The same drive control can be realized by applying a structure for applying the supply voltage Vsc. Incidentally, in this embodiment as well, in this embodiment, in each of the rows of the display panel 210 as a result of applying the individual selection signal Ssel from the selection driver 220 at different timings in the same manner as shown in FIG. Individual selection lines SL are arranged.

Therefore, according to the drive control method (display drive operation) of the display device, the same operation and advantages as the drive control method according to the first example described above can be obtained. In addition, the light emitting operation of the display pixel (optical element) is not executed, and the non-light emitting operation (black display operation) is executed in the section in which the pre-charging operation and the writing operation are performed on the display pixels in each row of the same group. . As a result, the flicker of the video can be suppressed, and the sharpness can be improved at the time of the display operation of the video by the continuous display of the plurality of video information items (still images).

Here, in the timing chart shown in FIG. 18, twelve rows of the display pixels PX constituting the display panel 210 are divided into three group sets, and the light emission operation is performed simultaneously at different timings for each group. The display device is controlled in such a way that it is executed. As a result, the black display interval rate (black insertion rate) becomes about 33% by non-luminescing operation in one frame period Tfr. Here, generally in human visual sensitivity, at least about 30% of the black insertion rate constitutes an indication of visual perception of moving images that are sharp and unconstrained from flicker. As a result, according to the driving control method, it is possible to realize a display device having desirable image quality.

(Third example)

Next, a third example of the drive control method applicable to the display apparatus according to the embodiment will be described with reference to the drawings.

20 is a timing chart showing a third example of the display control method of the display device according to the present embodiment.

Here, the description of the same drive control method as that of the above-described second example (refer to Fig. 18) is simplified.

As shown in FIG. 20, the third example of the drive control method of the display apparatus 200 according to the present embodiment is configured in the same manner as in the above-described second example. As a result, the threshold voltage detection operation is sequentially performed at a predetermined timing for each row with respect to all the display pixels PX disposed on the display panel 210, and then a plurality of rows of the display pixels PX not adjacent to each other. In each group determined by one group set of pixels disposed on the display panel 210, the pre-charge operation and the writing operation are performed by shifting the time with respect to the display pixel PX for each row included in the specific group. In order to execute sequentially in one frame section Tfr (approximately 16.7 msec), the display driving operation is executed by executing each group sequentially.

Here, in the display driving operation according to the present embodiment, for example, as shown in FIG. 20, all of the display pixels PX disposed on the display panel 200 are first, fourth, seventh, and the like. 3 groups in the display pixel PX in which 4 rows are set, such as a set of 10 rows, a set of 2, 5, 8, and 11 rows, and a set of 3, 6, 9, and 12 rows. Divided.

For example, in a group in which the display pixels PX are set to one group set in the first, fourth, seventh and tenth rows, the pre-charging operation and the writing operation are performed in order from the display pixels PX in the first row. Is executed. At the time when the writing operation is terminated with respect to the display pixel PX in the tenth row, four rows of the display pixels PX simultaneously emit light on the basis of the display data (gradation signal) written in each display pixel PX. Execute the action. This light emission operation is continued until the next pre-charge and next write operation is started with respect to the display pixels PX in the first row.

Further, at the time when the write operation is finished with respect to the display pixel PX in the tenth row, the pre-charge operation and the write operation are performed. The display pixels PX in the second, fifth, eighth and eleven rows are one group set. In the second row in the group set to, the display pixels PX of the display pixels PX are executed. In the following, the same operation is repeatedly executed until the pre-charging operation and the writing operation are finished with respect to the display pixels PX of the 12 rows of the next group.

In this manner, for each row of each group, the pre-charging operation and the writing operation are executed sequentially at a predetermined time. At the time when the write operation to the display pixels PX of all the rows included in the group is finished, all the display pixels PX of the group are driven and controlled to simultaneously perform the light emission operation. As a result, in the drive control operation according to the third example, in the same manner according to the second example, the display apparatus is provided with a section in which the pre-charging operation and the writing operation are executed with respect to the display pixels PX in different rows of the same group. In the above, all display pixels of the group are controlled in such a manner as to execute a non-light emitting operation (black display operation).

Further, in the same manner according to the second example described above, for example, in the period in which the pre-charging operation and the writing operation are performed with respect to the display pixels PX in the other row of the same group, the group from the power driver 230 The power supply voltage Vsc to which each power supply voltage line VL is applied is maintained at the low potential state Vsc, and the high potential power supply voltage Vsc = Ve is displayed for all rows included in the group. By the display apparatus being controlled in such a manner that the pixel PX is applied to the power supply voltage line VL of all the rows included in the group after the pre-charging operation and the writing operation are finished, such display apparatus operation can be realized. have. Incidentally, in the same manner as in the above-described second example (see FIG. 19), the configuration is such that the power supply voltage is applied in such a manner that a single power supply voltage Vsc is applied to the display pixels PX of all rows included in each group. The line VL may be branched and placed and applied.

Therefore, according to the drive control method (display drive operation) of the display device, in the same manner as the drive control method according to the second example described above, the display device is provided with 12 of the display pixels PX constituting the display panel 210. The rows are divided into a plurality of groups of display pixels, and the light emitting operation is performed simultaneously at different timings for each group. As a result, the non-light emitting operation (black display operation) is performed in a predetermined section of one frame section Tfr. In particular, in the present drive control method, since the black display section ratio (black insertion rate) can be set to about 33% by the non-light-emitting operation, a display device with improved clarity can be realized by suppressing flicker of the video. Can be.

Incidentally, the case where the display pixels PX constituting the display panel 200 are divided into three group sets in the driving control method according to the second and third examples. However, the present invention is not limited to this. For example, it is natural that the number of group sets is appropriately increased or decreased.

(Modified example of second and third example)

In the following, a modified example of the drive control method according to the second and third examples will be described.

21 is a timing chart showing a first modified example of the second example of the drive control method for the display apparatus according to the present embodiment.

22 is a timing chart showing a first modified example of the third example of the drive control method for the display apparatus according to the present embodiment.

23 is a timing chart showing a second modified example of the second example of the drive control method for the display apparatus according to the present embodiment.

21 is a timing chart showing a second modified example of the third example of the drive control method for the display apparatus according to the present embodiment.

In the modified example (first modified example) of the driving control method of the display apparatus according to the second and third examples, as shown in FIGS. 21 and 22, the display pixels constituting the display panel 210 ( PX) is divided into four groups (four groups: in FIG. 21, a set of first to third rows, a set of fourth to six rows, a set of seventh to ninth rows, a set of tenth to twelve rows; And in FIG. 22, four groups: sets of first, fifth and ninth rows, sets of second, sixth and tenth rows, sets of third, seventh and eleven rows, sets of fourth, eighth and twelve rows). The display apparatus is controlled in such a manner that the light emission operation is simultaneously executed at different timings for each group. In this case, in one frame section Tfr, the black display section ratio (black insertion rate) resulting from the non-luminescing operation is 25%. As a result, the flicker of the video becomes less than 30% which is an instruction without the flicker of the video as described above, but a display device having a relatively good picture quality can be realized.

Further, in the second modified example of the drive control method of the display apparatus according to the second and third examples, as shown in, for example, FIGS. 23 and 24, display pixels PX constituting the display panel 210. ) Are divided into two sets of groups (in FIG. 23, two groups into sets of first to sixth rows and sets of seventh to twelve rows; in FIG. 24, a set of odd rows and an even row Into 2 groups). The display apparatus is controlled in such a manner that each group is executed simultaneously at different timings. In this case, the black display interval rate (black insertion rate) becomes 50% in excess of 30%, which is the flicker-free instruction of the video as described above, by the non-luminescing operation in one frame period Tfr. The light emitting operation section is only half the frame Tfr, which is not possible to display image information at sufficient luminance. In addition, the image information may be provided at a sufficient luminance to obtain desired image quality.

(Fourth example)

Next, a fourth example of the drive control method applicable to the display apparatus according to the present embodiment will be described with reference to the drawings.

25 is a timing chart showing a fourth example of the drive control method for the display device according to the present embodiment. Here, the description of the same drive control method as the first to third examples (see Figs. 17 to 24) described above will be simplified. In addition, Fig. 26 is a configuration diagram of an essential part showing one example of the display apparatus for realizing the fourth example of the drive control method of the display driving apparatus according to the embodiment. Here, the same element as the display device according to the present embodiment described above is described by attaching the same reference numerals and symbols.

In the fourth example of the drive control operation of the display apparatus 210 according to the present embodiment, as shown in FIG. 25, in the same manner as in the first to third examples described above, the threshold voltage detection is performed by the display panel 210. 1) of the first half (one frame section Tfr) of one frame section Tfr (about 16.7 msec) after being sequentially executed at a predetermined timing with respect to all display pixels PX disposed on In each of the rows disposed on the display panel 210 in each of two rows), sequentially executed in a time shift of the pre-charge operation and the write operation with respect to the display pixel PX, and thus all the rows disposed on the display panel 210. By causing the display pixels PX in the row to simultaneously perform the light emission operation with the luminance gradation corresponding to the display data in the second half of one frame Tfr (half section of one frame section Tfr) D The splay drive operation is executed.

In this manner, the pre-charging operation and the writing operation are executed by driving control of the display apparatus so that all the display pixels PX simultaneously execute the light emitting operation at the time when the writing operation is performed on the display pixels PX of all the rows. In the interval, the display apparatus is controlled in such a manner that the light emitting operation is not performed with respect to the display pixels PX of several rows, and that all display pixels PX perform the non-light emitting operation (black display operation).

The display driving operation is, for example, applied to the power supply voltage lines VL of all rows from the power driver 230 in a section in which the pre-charging operation and the writing operation are performed with respect to the display pixels PX of each row. The power supply voltage (Vsc = Ve) is maintained at the low potential (Vs), and the high potential power supply voltage (Vsc = Ve) after the pre-charging operation and the writing operation are terminated with respect to the display pixels PX in all rows. Can be realized by controlling the display device in such a way that it is applied to the power supply voltage lines VL in all rows.

In the same drive control operation, for example, as shown in FIG. 26, a single power supply voltage line VL branches in all rows, and a single power supply voltage Vsc is divided into all display pixels PX. By applying the configuration in common with all the display pixels (PX) disposed on the display panel 210 to apply simultaneously to), and a single applied from the power supply unit 230 to the display pixels (PX) of all rows It may be realized by applying the power supply voltage Vsc. In the case of the configuration of the power driver 230, for example, at a predetermined time based on the power control signal supplied from the system controller 250, the high potential power supply voltage (Vsc = Ve) and the low potential power supply voltage ( Vsc = Vs) may be selectively output. For this reason, at least the shift register circuit cannot be provided as shown in FIG. Incidentally, in this embodiment, the individual selection lines SL are arranged for each row of the display panel 210, so that the individual selection signals Ssel are selected at different timings in the same manner as shown in FIG. 220).

As a result, according to the drive control method (drive control operation) of the display device, the display drive section (one frame section Tfr) is divided into two sections, the first half section and the second half section, and thus pre-charge The operation and the writing operation are executed sequentially with the display pixels of each row in the first half section and all the display pixels execute the light emitting operation simultaneously in the second half section. As a result, the black display section ratio (black insertion rate) having light emission in one frame section Tfr becomes 50% exceeding 30%, which is an indication that the flicker of the video cannot be visually recognized. However, since the light emission operation is only half of one frame period Tfr, the image information cannot be displayed at sufficient luminance. Further, since the pre-charge section and the write operation section (especially the write operation section) are shortened in each row, there is a possibility that the time for sufficiently writing the display data (gradation signal) cannot be secured. However, the image information can be displayed at a sufficient luminance, so that the appropriate image quality can be obtained by appropriately increasing the emission luminance of each display pixel, and the current value of the gradation current can be increased.

Next, the fifth to eighth embodiments and modified examples of the drive control method of the display apparatus in which the threshold voltage detection operation is controlled to be executed for a specific row during each section of the frame section in the display driving operation will be described.

(Example 5)

27 is a timing chart showing a fifth example of the drive control method for the display device according to the present embodiment.

Here, the description regarding the drive control method (see Figs. 2 and 7) in the same case as the above-described display drive device 100 and display pixel PX (light emitting drive circuit DC) is simplified.

In the fifth example of the drive control operation of the display apparatus 200 according to the present embodiment, as shown in FIG. 27, the following two operations are performed to display image information in one screen portion of the display panel 210. Are sequentially repeated across all rows, and the two operations are: in a particular row of the display image PX disposed on the display panel 210 in one frame section (about 16.7 msec; With respect to the pixels, the light emitting driving switching element (thin film transistor; light emitting driving element) for controlling the light emitting state of the organic EL element (light emitting element) OEL of the light emitting driving circuit DC provided on each display pixel PX. A threshold voltage detection operation (threshold voltage detection section Tdec) of the threshold voltage (or a voltage element corresponding to the threshold voltage); And a gradation signal (gradation signal (corresponding to gradation signal) corresponding to the display data to cause the display pixels PX (organic EL elements OEL) in each row to execute light emission sections having luminance gradations corresponding to the display data (gradation signals). Idata) or the non-light emitting display voltage Vzero corresponds to the switching element (threshold voltage) with respect to the display pixel PX (light emitting drive circuit DC) for each row of the display panel 210. Display driving operation (display driving section Tcyc) for compensating the threshold voltage of the voltage element.

Here, in the threshold voltage detection operation (threshold voltage detection section Tdec), a series of driving controls include: display pixels PX (light emitting circuits) in a predetermined detection voltage Vpv in a specific row of display panel 210. A voltage application section Tpv to be applied to DC); A voltage converging operation (voltage convergence section Tcv) for converging the voltage element based on the detection voltage Vpv to the threshold voltage at the detection time of each switching element (thin film transistor Tr13); And a voltage read operation (voltage readout period) for measuring the threshold voltage Vth13 after voltage convergence for each display pixel PX and storing the threshold voltage as threshold voltage data for each display pixel PX.

In particular, in the display driving operation of the display apparatus according to the fifth example, the threshold voltage detection operation includes the series of driving control described above with respect to the display pixel PX in one specific row during each frame period in the successive frame periods. Are executed sequentially.

In particular, as shown in FIG. 27, in the display panel 210 having 12 rows of arranged display pixels PX, the threshold voltage detection operation is performed with respect to the display pixels PX of the first row of the first frame. And the threshold voltage detection data is stored in a corresponding memory area of the frame memory. In the first frame, after the threshold voltage detection operation is terminated with respect to the display pixels PX in the first row, the display driving operation described below for each row from the first row to the twelfth row is performed on the display panel 210. It executes sequentially about all the display pixel PX arrange | positioned at.

Next, in the second frame, the threshold voltage detection operation is performed with respect to the display pixel PX in the second row after the display driving operation is performed with respect to the display pixel PX in the first row, and the threshold detection. Data is stored in the corresponding memory area of the frame memory. Thereafter, the display driving operation is sequentially performed for each row with respect to the display pixels from the second row to the twelfth row of the display panel 210.

Next, in the third frame, the threshold voltage detection operation is performed on the display pixel PX in the third row after the display driving operation is performed on the display pixels PX in the first and second rows, and The threshold detection data is stored in the corresponding memory area of the frame memory. Thereafter, the display driving operation is sequentially performed for each row with respect to the display pixels from the third row to the twelfth row of the display panel 210.

Hereinafter, in the same manner, the threshold voltage detection operation is repeatedly performed sequentially with respect to the display pixel PX in the corresponding row up to 12 frames, where the threshold data (threshold voltage) is one of the display panels 210. It is stored in the frame memory with respect to the entire display pixel PX disposed in the screen portion of the.

That is, in the drive control method (threshold voltage detection operation) of the display apparatus according to the present embodiment, the threshold voltage detection operation is performed with respect to the display pixels PX of the plurality of rows of the display panel 210 in each frame period. And the last threshold voltage is detected (monitored) by setting the frame section in one cycle in the number of rows of the display panel.

In the drive control method of the display device according to the present embodiment, the threshold voltage of the light emitting drive switching element (thin film transistor) provided on the display pixel (light emitting drive circuit) is a specific row for each frame section (threshold voltage detection operation). After detecting and storing with respect to the display pixels, the pre-charge voltage corresponding to the detected threshold voltage is immediately converted before the display data is written to each display pixel (pre-charge operation). By applying to the transistor), the writing operation of the display data (gradation signal) and the light emitting operation of the light emitting element (organic EL element) are performed on the display pixels of each row arranged on the display panel. Thus, at the time of execution of the threshold voltage detection operation, the threshold voltage (in the Vth movement) of the light emitting drive switching element can always be monitored with respect to the display pixels in several rows arranged on the display panel. In addition, the voltage component (charge) corresponding to the intrinsic threshold voltage of the switching element (threshold voltage changed by the Vth shift) is maintained at the control terminal (between the gate and the source of the thin film transistor) of the switching element provided with each display pixel. It is possible to set the state (state where the threshold voltage is individually compensated). As a result, in the writing operation of the display data, only the voltage component corresponding to the display data can be added to be charged, so that the voltage component based on the display data can be written quickly and suitably.

(Example 6)

Next, a sixth example of the drive control method of the display apparatus according to the present embodiment will be described with reference to the drawings.

28 is a timing chart showing a sixth example of the drive control method for the display device according to the present embodiment.

Here, the description of the same drive control method as the above-described fifth example (see Fig. 27) will be simplified. In addition, the shaded portion in Fig. 27 shows the same operating state as in the fifth example described above. Here, as the configuration of the display apparatus, for example, the configuration shown in FIG. 19 described above is applied to realize the sixth example of the drive control method of the display apparatus according to the present embodiment.

In the sixth example of the drive control operation of the display apparatus according to the present embodiment, as shown in FIG. 28, the following two operations are executed to display image information on one screen portion of the display panel 210, These two operations are: first dividing the display pixel PX pre-positioned on the display panel 210 into a group of a plurality of adjacent rows of display pixels, and then displaying the display pixels in a specific row of a specific group in one frame interval. A threshold voltage detection operation (threshold voltage detection section Tdec) for detecting a threshold voltage with respect to the light emitting drive switching element (thin film transistor) in PX; And display pixels PX for each row of the display panel 210 so that a plurality of rows of display pixels PX for each row can simultaneously perform a light emitting operation having a luminance gradation corresponding to the display data (gradation signal). Operation of all the rows (pre-charge interval Tth, write operation) for writing the gray level signal (gradation current Idata or non-emitting display voltage Vzero) corresponding to the display data after compensating the threshold voltage The display driving operation is sequentially repeated over the section Twrt).

Here, in the drive control method according to the sixth example, first, all the display pixels PX disposed on the display panel 210 are divided into groups of a plurality of rows in advance. For example, as illustrated in FIG. 28, twelve rows of the display pixels PX constituting the display panel 210 may include first to fourth rows, fifth to eighth rows, and ninth to twelfth rows. By setting four rows of display pixels PX, such as rows, into one set, such as rows adjacent to each other, they are divided into groups.

In the first frame, the threshold voltage detection operation (threshold voltage detection section Tdec) is performed in the first row of the group in which the display pixels PX are set to one set in the first to fourth rows. PX), and the threshold detection data is stored in the corresponding frame memory of the frame memory. In the first frame, the display driving operation (pre-charging operation) with respect to all the display pixels PX disposed on the display panel 210 after the threshold voltage detection operation is terminated with respect to the display pixels PX in the first row. The write operation Tth + Twrt) is executed sequentially for each row from the first row to the twelfth row.

In the display driving operation for each row, the light emitting operation is performed with respect to the group in which the writing operation is terminated with respect to the display pixels PX of all rows included in each group. For example, in the group in which the display pixels PX in the first to fourth rows are set in one group set, the pre-charging operation and the writing operation are executed in order from the display pixels PX in the first row. . At the time when the writing operation is finished with respect to the display pixels PX of the fourth row, the four rows of display pixels PX in the group emit light based on the display data (gradation signal) written in each display pixel PX. Execute the action simultaneously. This light emission operation is continued until the next pre-charging operation and the writing operation are started with respect to the display pixels PX of the first row, or until the threshold voltage detection operation is started with respect to any of the first to fourth rows.

Further, at the time when the write operation is finished with respect to the display pixel PX in the fourth row, the pre-charge operation and the write operation are performed in a group in which the display panels in the fifth to eighth rows are set in one group set. It is executed in order from the display pixel PX in row 5. At the time when the writing operation is executed with respect to the display pixel PX in the eighth row, four rows of the display pixels PX in the group execute the light emitting operation simultaneously. In the following, the same operation is repeatedly performed with respect to the display pixel PX in each row of the next group.

Next, in the second frame, the pre-charging operation and the writing operation are executed sequentially in a group in which the display pixels PX in the first to fourth rows are set in one group set. When the time when four rows of the display pixels PX are simultaneously executed in the group executes the light emission operation, the threshold voltage detection operation (threshold voltage detection section Tdec) is performed by the display pixels PX in the fifth to eighth rows. ) Is performed with respect to the display pixels PX of the fourth row (corresponding to the first row in the group) in the group in which the set of one group is set. As a result, the pre-charging operation and the writing operation are executed sequentially in the group after the termination of the threshold voltage detection operation.

Next, the pre-charging operation and the writing operation are terminated in the group in which the display pixels PX in the fifth and eighth rows are set in one group set. At the time when four rows of the display pixels PX in the group simultaneously perform the light emission operation, the pre-charge operation and the write operation are performed such that the display panels PX in the ninth to twelfth rows are set to one group set. Executed sequentially in groups. Thereafter, four rows of display pixels PX in the group simultaneously perform the light emitting operation.

In the same way, for each group previously set during each frame period, the threshold detection operation is performed on the display pixel PX in a particular row included in the group. Further, when the write operation is finished with respect to the display pixels PX of all the rows included in each group, the display driving operation is performed so that all display pixels PX included in the group can execute the light emission operation at the same time. It is executed repeatedly.

In this manner, the threshold voltage detection operation is performed with respect to the display pixels PX of a particular row during each frame period, where the threshold voltage detection operation is performed with respect to the display pixels PX in several rows of the display panel 210. . As a result, the last threshold voltage is always detected (monitored) by setting the frame section in one cycle in the number of display panel rows.

Further, in the display driving operation according to the sixth example, in the interval of the threshold voltage detection operation, the write-charge operation and the write operation are performed with respect to the display pixels PX of the other rows in the same group, and the display apparatus is a group Performs a non-light emitting operation so that all display pixels are set to the non-light emitting display state (black display state).

For example, as shown in Figs. 7 and 12, at the time of threshold voltage detection operation, pre-charging operation, and writing operation, the low potential applied to the power supply voltage line VL in the row from the power driver 230. The power supply voltage (Vsc = Vs) is the high potential power in the power supply voltage line VL of all the rows in the group after the end of the threshold voltage detection operation, the pre-charge operation and the write operation for all rows included in the same group. By applying the supply voltage (Vsc = Ve), the threshold voltage detection, pre-charging operation, and writing operation are sequentially applied to the display pixels PX in the rows included in the same group in a sequential manner. By controlling the display device, the display driving operation can be realized.

In addition, a single power supply voltage line VL is displayed in the first to fourth rows (5th to 8th and 9th to 12th rows) to simultaneously apply a single power supply voltage Vsc to each group. By applying the configuration branched and commonly connected to the pixel PX, the same drive control can also be realized. Thus, the single power supply voltage Vsc applied from the power driver 230 is applied to the display pixel PX in all rows included in the same group. Incidentally, even in the driving control method of the present invention, in the same manner as shown in FIG. 16, the individual selection lines SL are arranged for each row, and the individual selection signals Ssel are selected at different timings. Is applied from the individual selection signal Ssel.

Therefore, depending on the drive control method (display drive operation) of the display device, the same operation and advantages as the drive control method according to the fifth example described above can be obtained. In addition, in the period in which the threshold voltage detection operation, the pre-charging operation and the writing operation are performed with respect to the display pixels in each row of the same group, the light emitting operation of the display pixel (light emitting element) is not performed, but the non-light emitting operation ( Black display operation) is executed. As a result, the flicker of the moving picture can be suppressed at the time of the display operation of the moving picture by the continuous display of the plurality of pieces of image information, and the sharpness thereof is improved.

Here, in the timing chart shown in FIG. 28, twelve rows of the display pixels PX constituting the display panel 210 are divided into three group settings, and the light emission operation is performed simultaneously at different timings for each group. Is executed. For this reason, the black display section ratio (black insertion rate) becomes about 33% by the non-light emitting operation. Here, generally in human visual sensitivity, at least about 30% of the black insertion rate constitutes an indication of visual perception of moving images that are sharp and unconstrained from flicker. As a result, according to the driving control method, it is possible to realize a display device having desirable image quality.

(Example 7)

Next, a seventh example of the drive control method of the display apparatus according to the present embodiment will be described with reference to the drawings.

29 is a timing chart showing a seventh example of the drive control method for the display device according to the present embodiment.

Here, the description of the same drive control method as the sixth example (see Fig. 28) is simplified.

In the seventh example of the driving control operation of the display apparatus 210 according to the present embodiment, as shown in FIG. 20, the following two operations are sequentially performed to display image information of one screen unit of the display panel 210. And these two actions are:

The display pixels PX are first divided in groups in rows not adjacent to each other, and the threshold voltages are set for the light emitting driving switching elements (thin film transistors) of the display pixels PX in a specific row of a specific group in one frame period. A threshold voltage detection operation (threshold voltage detection section Tdec) for detecting; And a plurality of rows of display pixels PX (organic EL elements) for each row to simultaneously perform light emission operations with luminance gradations corresponding to display data (gradation signals) at predetermined timings. After compensating the threshold voltage with respect to the display pixels PX of the rows included in the group, writing a gray level signal (gradation current Idata or non-emitting display voltage Vzero) corresponding to the display data (pre-charge) A display driving operation for sequentially executing the section Tth and the write operation section Twrt.

Here, in the driving control method according to the seventh example, in particular, all the display pixels PX disposed on the display panel 210, for example, as shown in FIG. 29, display the display panel 210. The twelve rows of the constituting display pixels PX comprise a set of first, fourth, seventh and tenth rows, a set of second, five, eight and eleven rows, and a set of third, sixth, ninth and twelfth rows. Likewise, by setting each of the four rows of display pixels PX to one set, it is divided into three groups.

In the first frame, the threshold voltage detection operation (threshold voltage detection interval Tdec) is performed by the first row of the group in which the display pixels PX are set as one group set in the first, fourth, seventh, and tenth rows. Is executed with respect to the display pixel PX. Thereafter, the display driving operation (pre-charging operation and writing operation; Tth + Twrt) is executed starting from the order in which the row numbers are small for each group with respect to all the display pixels PX disposed on the display panel 210. .

In the display driving operation for each row, the light emitting operation is performed with respect to the group in which the writing operation is terminated with respect to the display pixels PX of all rows included in each group. For example, in the group in which the display pixels PX of the first, fourth, seventh and tenth rows are set in one group set, the pre-charging operation and the writing operation are performed in order from the display pixels PX in the first row. Is executed. At the time when the writing operation ends with respect to the display pixels PX of the tenth row, four rows of the display pixels PX in the group emit light based on the display data (gradation signal) written in each display pixel PX. Execute the action at the same time. This light emitting operation until the next pre-charging operation and writing operation is started with respect to the display pixels PX of the first row or until the threshold voltage detection operation is started with respect to any of the first, fourth, seventh and tenth rows. Is continuous.

Also, at the time when the write operation is terminated with respect to the display pixel PX in the tenth row, the pre-charge operation and the write operation are set to the group of display panels in the second, fifth, eighth and eleven rows as one group set. Are executed in order from the display pixels PX in the second row. Then, at the time when the write operation is executed with respect to the display pixel PX in the eleventh row, four rows of the display pixels PX in the group execute the light emission operation simultaneously. In the following, the same operation is repeatedly performed with respect to the display pixel PX in each row of the next group.

Next, in the second frame, the pre-charging operation and the writing operation are executed sequentially in a group in which the display pixels PX in the first, fourth, seventh and tenth rows are set to one group set. When four rows of display pixels PX in the group execute light emission operations simultaneously, the threshold voltage detection operation (threshold voltage detection interval Tdec) is performed by the display pixels PX in the second, fifth, eighth and eleven rows. It is executed with respect to the display pixels PX of the second row (corresponding to the first row of the group) in the group set to this one group set. As a result, the pre-charging operation and the writing operation are executed sequentially in the group after the termination of the threshold voltage detection operation.

Next, the pre-charging operation and the writing operation are terminated in the group in which the display pixels PX in the second, fifth, eighth and eleven rows are set to one group set. Then, at the time when four rows of the display pixels PX in the group execute the light emission operation simultaneously, the pre-charge operation and the write operation, the four rows of the display pixels PX in the group execute the light emission operation simultaneously. do.

In the same way, for each group previously set during each frame period, the threshold detection operation is performed on the display pixel PX in a particular row included in the group. Further, when the writing operation is finished with respect to the display pixels PX of all the rows included in each group, the display driving operation is repeatedly performed so that all the display pixels PX of the group can execute the light emission operation at the same time. Is executed.

In this manner, by sequentially and repeatedly executing the threshold voltage detection operation with respect to the display pixels PX of a particular row during each frame period, the threshold voltage detection operation is displayed on several rows of the display panel 210 in each frame period. It is executed with respect to the pixel PX. As a result, the last threshold voltage is always detected (monitored) by setting the frame section in one cycle in the number of display panel rows.

Further, in the display driving operation according to the sixth example, in the interval of the threshold voltage detection operation, the write-charge operation and the write operation are performed with respect to the display pixels PX of the other rows in the same group, and the display apparatus is a group Performs a non-light emitting operation so that all display pixels are set to the non-light emitting display state (black display state).

In addition, the power supply voltage line VL of each row of the group from the power driver 230 in a section in which the threshold voltage detection operation, the pre-charge operation and the write operation are performed with respect to the display pixel PX in another row of the same group. The applied power supply voltage Vsc is maintained at low potential Vs, and the high potential power supply voltage Vsc = Ve is a threshold voltage detection operation with respect to the display pixels PX of all rows of the same group, By controlling the display device in such a manner that it is applied to the power supply voltage lines VL of all the rows included in the group after the pre-charge operation and the end of the write operation, such display device operation can be realized. Incidentally, in the same manner as in the above-described second example (see FIG. 19), the configuration is such that a single power supply voltage Vsc is applied to the display pixels PX of all rows included in each group. VL) can be branched and placed and applied.

As a result, according to the drive control method (display drive operation) of the display device, the same operation and advantages as the drive control method according to the fifth example described above can be obtained. On the other hand, in the same manner as the drive control method according to the sixth example, in the display apparatus, twelve rows of display pixels PX constituting the display panel 210 are divided into a plurality of group sets of display pixels, and light emission The operation is executed simultaneously at different timings for each group. Therefore, the non-light emitting operation (black display operation) is performed in a predetermined section of one frame section. In particular, in the present drive control method, since the black display interval rate (black insertion rate) can be set to about 33% by the non-light-emitting operation, as a result, the display device suppresses the flicker of the moving picture, and the sharpness thereof. Can be realized by improving.

Incidentally, in the driving control method according to the sixth and seventh examples, the case in which the display pixels PX constituting the display panel 200 are divided into three group sets has been described. However, the present invention is not limited to this. For example, it is natural that the number of group sets is appropriately increased or decreased.

(Modified examples of the sixth and seventh examples)

In the following, a modified example of the drive control method according to the second and third examples will be described.

30 is a timing chart showing a first modified example of the sixth example of the drive control method for the display apparatus according to the present embodiment.

31 is a timing chart showing a first modified example of the seventh example of the drive control method for the display apparatus according to the present embodiment.

32 is a timing chart showing the second modified example of the sixth example of the drive control method for the display apparatus according to the present embodiment.

33 is a timing chart showing the second modified example of the seventh example of the drive control method for the display apparatus according to the present embodiment.

In the first modified example of the driving control method of the display apparatus according to the sixth and seventh examples, as shown in FIGS. 30 and 31, the display pixels PX constituting the display panel 210 are divided into four groups. Divided into sets (in FIG. 30, sets of first to third rows, sets of fourth to sixth rows, sets of seventh to ninth rows, sets of four groups of sets of tenth to twelve rows; and in FIG. 4 sets of 1st, 5th and 9th rows, 2nd, 6th and 10th rows, 3rd, 7th and 11th rows, 4th group of 4th, 8th and 12th rows), and threshold voltage While the detection operation is performed with respect to the display pixel PX in a specific row during each frame period, the pre-charge operation and the writing operation are executed with respect to the display of each row at different timings for each group, and then simultaneously execute the light emission operation. . In this case, the black display interval rate (black insertion rate) becomes about 25% by non-luminescence operation in one frame period. Although the ratio is less than 30%, which is an indication that the flicker cannot be visually seen, a display device having a relatively good image quality can be realized.

Further, in the second modified example of the driving control method of the display apparatus according to the sixth and seventh examples, for example, as illustrated in FIGS. 32 and 33, display pixels PX constituting the display panel 210 are provided. ) Is a set of two groups (two sets of sets: a set of first to sixth rows and a set of seventh to twelve rows; and two sets of sets: a set of odd rows in FIG. And a set of even rows, so that the threshold voltage detection operation is performed with respect to the display pixel PX in a particular row during each frame period, while the pre-charge operation and the write operation are performed at different timings for each group. It is controlled in such a manner that the light emitting operation is executed simultaneously after being executed with respect to the display of each row.

In this case, the black display interval rate (black insertion rate) is 50% by non-light emitting operation in one frame period. The flicker of the video exceeds 30%, which is an invisible indication. However, since the light emitting operation section is only half the frame, the image information cannot be displayed at sufficient luminance gradation. Then, by appropriately increasing the luminous luminance of each display pixel, the image information can be displayed at a sufficient luminous luminance, and can have good image quality.

(Example 8)

Next, an eighth example of the drive control method of the display apparatus according to the present embodiment will be described with reference to the drawings.

34 is a timing chart showing a fourth example of the drive control method for the display device according to the present embodiment.

Here, the description of the same drive control method as the fifth to seventh examples (see FIGS. 27 to 33) will be simplified. Here, for example, as the configuration of the display apparatus for realizing the eighth example of the drive control method of the display apparatus according to the present embodiment, the configuration shown in Fig. 26 can be applied.

In an eighth example of the drive control operation of the display apparatus 200 according to the present embodiment, as shown in FIG. 34, switching for light emission driving of the display pixels PX in a specific row disposed on the display panel 210. The threshold voltage detection (threshold voltage detection section Tdec) for detecting the threshold voltage with respect to the element (thin film transistor) is first performed in the first half of one frame section (half section of one frame section). . Thereafter, the pre-charging operation and the writing operation are performed such that the display pixels PX of all the rows disposed on the display panel 210 are divided into the second half of one frame period (1/2 of one frame period Tfr). Display pixels PX of all rows arranged on the display panel 210 for each row as a shift of time for executing the display driving operation to simultaneously execute the light emitting operation having the luminance gradation corresponding to the display data in the section). Are executed sequentially with respect to. As a result, image information is displayed on one screen of the display 210.

In this manner, the threshold voltage detection operation is performed with respect to the display pixels PX in a particular row during each frame period, while driving control of the display device is executed, so that all display pixels PX are controlled in each frame period. In both half, the light emission operation is executed simultaneously. As a result, the display apparatus is controlled so that in the first half of each frame section in which the threshold voltage detection operation, the pre-charge operation and the writing operation are performed, the light emission operation is not performed with respect to the display pixels PX of several rows, However, the non-luminescing operation (black display operation) executes all the display pixels PX.

The high potential power supply voltage Vsc = Ve is applied to the power supply voltage lines VL of all the rows after the threshold voltage detection operation, the pre-charge operation, and the write operation are completed for the display pixels PX of all the rows. The power supply voltage applied from the power supply unit 230 to the supply power lines VL of all the rows in the period in which the threshold voltage detection operation, the pre-charge operation and the write operation are performed with respect to the display pixels PX of each row, The display driving operation can be realized by controlling the display apparatus in such a manner as to maintain Vsc).

In the same drive control operation, for example, as shown in FIG. 26, a single power supply voltage line VL branches in all rows, and a single power supply voltage Vsc is divided into all display pixels PX. By applying the configuration in common with all the display pixels (PX) disposed on the display panel 210 to apply at the same time, thereby applying a single applied from the power supply unit 230 to the display pixels (PX) of all rows It may be realized by applying a power supply voltage.

In the case of the configuration of the power driver 230, for example, at a predetermined time based on the power control signal supplied from the system controller 250, the high potential power supply voltage (Vsc = Ve) and the low potential power supply voltage ( Vsc = Vs) may be selectively output. For this reason, at least the shift register circuit cannot be provided as shown in FIG. Incidentally, in this driving control method, the individual selection lines SL are arranged for each row of the display panel 210 in the same manner as shown in Fig. 16, and the individual selection signals Ssel are selected at different timings. It is applied from the driver 220.

As a result, according to the driving control method (display driving operation) of the display device, each frame section is divided into two sections, the first half section and the second half section, and the threshold voltage detection operation is applied to the display pixels of a specific row. After being executed with respect to the display device, the display apparatus is controlled in such a manner that all the pixels simultaneously execute the light emission operation in the second half section while the pre-charge operation and the writing operation are sequentially executed in the first half section. As a result, the black display section ratio (black insertion rate) becomes 50% by the light emission operation in one frame section. Therefore, the flicker of the video exceeds 30% of the instructions which cannot be seen visually. The image information cannot be displayed at sufficient light emission luminance, and the pre-charging operation and the writing operation (in particular, the writing operation) in each row are shortened. For this reason, there is a possibility that the time for writing the display data cannot be secured. Further, by appropriately increasing the light emission luminance of each display pixel and increasing the current value of the gradation current, the image information can be displayed at a sufficient light emission luminance and good image quality can be obtained.

Various embodiments and modifications may be made without departing from the spirit and scope of the invention. The above-described embodiments are intended to illustrate the present invention without limiting the technical scope of the present invention. The technical scope of the present invention is explained by the attached embodiments rather than the embodiments. Various modifications are intended to be within the meaning of equivalent claims of the invention and within the claims contemplated by the scope of the invention.

Claims (42)

A display driving device for operating the current controlled optical element OEL of each display pixel PX provided with an optical element OEL and a driving element TR13 for supplying a driving current to the optical element in accordance with the display data. ego, A gradation signal generation circuit 130 for generating a gradation signal corresponding to the luminance gradation of the display data and supplying the gradation signal to the display pixel; A threshold voltage detection circuit (140) for detecting an intrinsic threshold voltage of the driving element of the display pixel; And And a compensation voltage applying circuit 150 generating a compensation voltage for compensating the threshold voltage of the driving device based on the threshold voltage, and applying the compensation voltage to the driving device. Device. The method of claim 1, And a memory circuit 170 for storing threshold data corresponding to the threshold voltage detected by the threshold voltage detection circuit 140, And the compensation voltage applying circuit (150) generates the compensation voltage based on the threshold data stored in the memory circuit. The method of claim 1, And a detection voltage applying circuit 150 for applying a threshold detection voltage having a potential higher than the threshold voltage to the driving element. In the threshold voltage detection circuit 140, the threshold voltage detection voltage is applied to the driving element by the detection voltage application circuit 150, whereby a part of the charge corresponding to the threshold voltage detection voltage is discharged and converged. And a voltage as said threshold voltage afterwards. The method of claim 3, wherein The driving device includes a current path for allowing the driving current to flow through the optical device, and a control terminal for controlling a supply state of the driving current, The detection voltage application circuit applies the threshold detection voltage between the control terminal of the drive element and one end side of the current path, and And the threshold voltage detection circuit detects a potential difference as the threshold voltage between the control terminal of the drive element and the one end side of the current path when no current flows in the current path. Device. The method of claim 4, wherein The compensation voltage applying circuit 150 applies the compensation voltage based on the threshold data stored in the memory circuit between the control terminal of the driving element and the one end side of the current path. Display drive. The method according to any one of claims 1 to 5, Each optical element OEL has a light emitting element for performing a light emitting operation at a luminance corresponding to the current value of the applied current, and The gradation signal generating circuit 130 includes a circuit for generating a gradation current as the gradation signal having a current value to cause the light emitting element to execute a light emitting operation with a gradation corresponding to the luminance gradation of the display data. Display drive device characterized in that. The method according to any one of claims 1 to 5, Each optical element OEL includes a light emitting element for performing a light emitting operation at a luminance corresponding to a current value of an applied current, and The gradation signal generating circuit 130 includes a circuit for generating a non-luminous display voltage as the gradation signal having a predetermined voltage value to cause the light emitting element to execute a non-luminous operation. Display drive. The method according to any one of claims 1 to 5, A single data line DL corresponding to the display pixel, a signal path for detecting the threshold voltage with the threshold voltage detection circuit, a signal path for applying the compensation voltage to the compensation voltage application circuit, and the And a signal path switching circuit (180) for selectively switching and controlling a connection between the signal paths for supplying the gray level signals to the gray level signal generation circuit. The method of claim 8, The signal path switching circuit 180 selectively switches and controls the connection between the signal path for applying the threshold detection voltage and the single data line DL to the detection voltage applying circuit. Device. A display device for displaying image information corresponding to the display data, The current control optical element OEL and each of the crossing points of the plurality of selection lines SL and the plurality of data lines DL arranged to extend in each row direction and in each column direction, respectively. A display panel 210 having a plurality of display pixels PX, each of which includes a driving element Tr13 for supplying a driving current; A selection driving unit (220) for sequentially supplying selection signals to the plurality of selection lines of the display panel, and sequentially setting the display pixels in each row to a selection state; And A data driving unit 240; The data driving unit 240, A gradation signal generation circuit (130) for generating a gradation signal corresponding to the luminance gradation of the display data and supplying the gradation signal to the display pixels through the respective data lines; A threshold voltage detection circuit (140) for detecting an intrinsic threshold voltage of the driving element of each display pixel through each data line; And A compensation voltage applying circuit 150 generating a compensation voltage for compensating the threshold voltage of each display pixel based on the respective threshold voltages, and applying the compensation voltage to each display pixel through each data line; Display device comprising a. The method of claim 10, The data driving unit 240 further includes a memory circuit 170 for storing threshold data corresponding to the threshold voltage detected by the threshold voltage detection circuit 140, and And the compensation voltage applying circuit (150) generates the compensation voltage based on the threshold data stored in the memory circuit (170). The method of claim 10, The data driving unit 240 further includes a detection voltage applying circuit 150 for supplying a threshold detection voltage having a potential higher than the threshold voltage to the driving element of each display pixel through each data line. Includes, and The threshold voltage detection circuit 140 may apply the threshold voltage detection voltage to the driving device through each of the data lines, so that a part of the electric charge corresponding to the threshold voltage detection voltage is discharged and converged. And detecting a voltage as the threshold voltage through a line. The method of claim 12, The driving element Tr13 includes a current path through which the driving current flows to the optical element, and a control terminal for controlling a supply state of the driving current. The detection voltage application circuit 150 applies a threshold detection voltage between the control terminal of the drive element and one end side of the current path, and The threshold voltage detection circuit 140 has a potential difference as the threshold voltage between the control terminal of the driving element and the one end side of the current path when no current flows in the current path through each of the data lines. Display device characterized in that for detecting. The method of claim 13, The compensation voltage applying circuit 150 applies the compensation voltage based on the threshold data stored in the memory circuit between the control terminal of the driving element and the one end side of the current path through each data line. Display device, characterized in that. The method according to any one of claims 10 to 14, And each optical element (OEL) has a light emitting element for executing a light emitting operation at a luminance corresponding to the current value of the applied current. The method of claim 15, The light emitting device is a display device comprising an organic electroluminescent device. The method of claim 15, The gradation signal generating circuit 130 includes a circuit for generating a gradation current as the gradation signal having a current value to cause the light emitting element to execute a light emitting operation with a gradation corresponding to the luminance gradation of the display data. Display device, characterized in that. The method of claim 15, The gradation signal generating circuit 130 includes a circuit for generating a non-luminous display voltage as the gradation signal having a predetermined voltage value to cause the light emitting element to execute a non-luminous operation. Display device. The method of claim 11, The data driving unit 240, A threshold acquisition circuit (110) for individually reading each threshold data corresponding to each threshold voltage detected from each of the plurality of display pixels through each data line, and sequentially transmitting the respective threshold data; And And a data acquiring circuit 110 which sequentially and individually retrieves and maintains the luminance gray scale data for generating the gray scale signal with respect to each of the display pixels. The memory circuit 170 individually stores each of the threshold data transmitted from the threshold acquisition circuit 110 corresponding to each of the plurality of display pixels, and The gradation signal generating circuit 130 generates the gradation signal corresponding to the luminance gradation held by the data acquisition circuit 110, and transmits the gradation signal to each display pixel through the respective data lines. Display device characterized in that the supply. The method of claim 19, And a configuration for sequentially and separately loading the luminance grayscale data into the data acquisition circuit, and a configuration for sequentially loading the threshold data by reading the threshold data in the threshold acquisition circuit. The method of claim 10, The data driving unit 240 includes a single data line DL corresponding to the display pixel, each signal path for detecting the threshold voltage by the threshold voltage detection circuit 140, and the compensation voltage applying circuit. And a signal path switching circuit 180 for selectively switching and controlling a connection between the signal path for applying the compensation voltage to 150 and the signal path for supplying the gray level signal to the gray level signal generating circuit. Display device. The method of claim 21, And the signal path switching circuit (180) selectively switches and controls a signal path for applying the threshold detection voltage to the detection voltage application circuit and a connection between the single data line. The method of claim 10, A power driving unit 230 for applying a predetermined power supply voltage to each of the plurality of display pixels; The power supply unit 230 sequentially applies the power supply voltage to the display pixels of each row of the display panel at a predetermined timing, thereby setting the display pixels of each row to an operating state. Display device. The method of claim 10, A power driving unit 230 for applying a predetermined power supply voltage to each of the plurality of display pixels; The power supply unit 230 supplies the power supply to the display pixel for each group obtained by dividing the power supply at a predetermined timing into sets for each of the plurality of display pixels disposed on the display panel. And sequentially applying the display pixels to set the display pixels of each group to an operating state. The method of claim 10, And a drive control unit (250) for generating a timing control signal for controlling the timing of the operation of detecting the threshold voltage by the threshold voltage detection circuit (140). The method of claim 25, The driving control unit 250 is configured to supply the gray level signal to all of the plurality of display pixels disposed on the display panel by the selection driving unit 220 and the data driving unit 240. And let the threshold voltage detection circuit (140) detect the threshold voltage of the drive element of the display pixels in the other row of the display panel with the timing control signal. The method of claim 25, The driving control unit 250 is configured to supply the gray level signal to all of the plurality of display pixels disposed on the display panel by the selection driving unit 220 and the data driving unit 240. And causing the threshold voltage detection circuit (140) to detect the threshold voltage of the drive element of the display pixel in the adjacent row of the display panel with the timing control signal. The method of claim 10, Each of the driving pixels includes a driving circuit DC for controlling the operation of the optical device. The driving circuit DC is: A first switch circuit Tr13 connected at one end of the current path to the power supply voltage and at another end of the current path to a contact point N12 to the optical element; A control terminal is connected to the selection line SL, one end of the current path is applied to the power supply voltage, and the other end of the current path is connected to the control terminal of the first switch circuit Tr13. A second switch circuit Tr11; And A control terminal is connected to the selection line SL, one end of the current path is applied to the data line DL, and another end of the current path is connected to the contact point N12. A circuit Tr12, The driving device is the first switch circuit, and the detection voltage application circuit applies the threshold detection voltage between the control terminal and the contact point of the first switch circuit. The threshold voltage detection circuit 140 detects a potential as the threshold voltage between the control terminal of the first switch circuit and the contact point, and The compensation voltage applying circuit (150) is characterized in that for applying the compensation voltage between the control terminal and the contact point of the first switch circuit. The method of claim 28, And each of the first to third switch circuits includes a field effect transistor provided as a semiconductor layer constituting amorphous silicon. In the drive control method of the display driving device for operating the current controlled optical element (OEL) of the display pixel (PX) provided with an optical element (OEL) and a drive element (Tr13) for supplying a drive current to the optical element, Detecting an intrinsic threshold voltage of the drive element; Generating a compensation voltage for compensating the threshold voltage of the driving element based on the threshold voltage, and applying the compensation voltage to maintain the voltage as a voltage component; And Supplying a gradation signal to the display pixel, adding a voltage component based on the gradation signal to the voltage component based on the compensation voltage, and allowing the driving element to maintain the voltage component; The drive control method of the display drive device characterized in that. The method of claim 30, Detecting the threshold voltage comprises storing threshold data corresponding to the threshold voltage, and The operation of storing the threshold data by detecting the threshold voltage is performed at a time before the step of applying the compensation voltage to the driving element and maintaining the voltage component based on the gray level signal. Drive control method of display drive device. The method of claim 30, Detecting the threshold voltage includes: Applying a threshold detection voltage having a potential higher than the threshold voltage; And And detecting a voltage as the threshold voltage after a portion of the charge corresponding to the threshold voltage detection voltage is discharged and converged. The method of claim 30, Each optical element has a light emitting element for performing a light emitting operation at a luminance corresponding to the current value of the applied current, The step of adding a voltage component based on the gradation signal to the voltage component based on the compensation voltage and causing the driving element to hold the voltage component include: When the light emitting element causes the light emitting operation to execute the light emitting operation at a luminance corresponding to the luminance gray scale of the display data, a current value for causing the light emitting element to execute the light emitting operation at the luminance corresponding to the luminance gray scale of the display data Generating a gradation current as the gradation current, and supplying the gradation current to the display pixel; And Generating a non-light-emitting display voltage as the gradation signal having a predetermined voltage value in order to cause the optical element to perform a non-light emitting operation when the light emitting element executes a non-light emitting operation; And supplying said non-luminous display voltage to said display pixel. In a driving control method of a display apparatus for displaying image information corresponding to display data, the current control optical element OEL and a plurality of selection lines SL arranged to extend in each row direction and in each column direction, respectively. And a display panel 210 having a plurality of display pixels PX, each of which includes a driving element Tr13 for supplying a driving current to the optical element at each intersection of the plurality of data lines DL. The method is: Detecting an intrinsic threshold voltage of the drive element of each display pixel; Generating a compensation voltage for compensating the threshold voltage of the drive element based on the threshold voltage, applying the compensation voltage to the drive element of each display pixel, and maintaining the compensation voltage as a voltage component Making a step; Supplying a gradation signal to each display pixel, adding a voltage component based on the gradation signal to the voltage component based on the compensation voltage, and allowing the driving element of each display pixel to maintain the voltage component. To make it; And Supplying the driving current generated based on the voltage component held by the driving element of each display pixel to the optical element, and causing the optical element to operate according to the gradation signal; A drive control method for a display device, characterized in that The method of claim 34, wherein Detecting the threshold voltage includes: Applying a threshold detection voltage having a potential higher than the threshold voltage to the drive element of each display pixel; And And detecting a voltage as the threshold voltage after a portion of the charge corresponding to the threshold detection voltage is discharged and converged. The method of claim 34, wherein Detecting the threshold voltage includes: Storing threshold data corresponding to the threshold voltage, and The step of storing the threshold data by detecting the threshold voltage comprises: disposing the threshold data on the display panel before the step of applying the compensation voltage to the driving element and maintaining the voltage component based on the gray level signal. And a plurality of all display pixels. The method of claim 36,  And storing the threshold data by detecting the threshold voltage is sequentially performed with respect to the plurality of display pixels for each row disposed on the display panel. The method of claim 34, wherein Detecting the threshold voltage includes: Storing threshold data corresponding to the threshold voltage, and By detecting the threshold voltage, storing the threshold data comprises: displaying the display in another row of the display panel during each operation period in which the gradation signal is supplied to all of the plurality of display pixels disposed on the display panel. And a drive control method for the display device. The method of claim 34, wherein Detecting the threshold voltage includes: Storing threshold data corresponding to the threshold voltage, and By detecting the threshold voltage, storing the threshold data comprises: displaying the display in a close row of the display panel during each operation period in which the gray level signal is supplied to all the plurality of display pixels disposed on the display panel. And a drive control method for a pixel. The method of claim 34, wherein Adding a voltage component based on the gradation signal to the voltage component based on the compensation voltage and causing the driving element of each display pixel to maintain the voltage component include: each row disposed on the display panel. And sequentially executed with respect to the plurality of display pixels, and causing the optical element to be executed in accordance with the gradation signal, adding a voltage component based on the gradation signal to the voltage component based on the held compensation voltage. The drive control method of the display device, characterized in that executed in sequence from the end of the row. The method of claim 34, wherein The step of adding a voltage component based on the gradation signal to the voltage component based on the gradation signal, and causing the driving element of each display pixel to hold the voltage component on the display panel for each row Executed sequentially for each group obtained by grouping the plurality of display pixels disposed in, and The operation of causing the optical element to execute a light emission operation with a luminance gradation corresponding to the gradation signal includes: adding a voltage component based on the gradation signal to the voltage component based on the gradation signal to be maintained. A drive control method for a display device, characterized in that executed sequentially from the group. The method according to any one of claims 34 to 41, Each of the optical elements has a light emitting element for performing a light emitting operation at a luminance corresponding to the current value of the applied current, and The step of adding a voltage component based on the gradation signal to the voltage component with respect to the compensation voltage and causing the driving element to hold the voltage component: When the light emitting element of each display element causes the light emitting operation to execute the light emission operation at a luminance corresponding to the gradation luminance of the display data, the light emitting element causes the light emission operation to be executed at the luminance corresponding to the gradation luminance of the display data. Generating a gradation current as the gradation current having a current value, and supplying the gradation current to the display pixel; And In the case where the light emitting element of each display element causes the non-light emitting operation, the non-light emitting display voltage as the gradation signal having a predetermined voltage to cause the optical element to execute the non-light emitting operation Generating and supplying the non-luminous display voltage to the display pixel.

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