JP2008180836A - Display device having partial display function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device having a partial display function with a small amount of circuits and low power consumption. <P>SOLUTION: A pixel circuit 14 is provided with a TFT 19 for non-display data writing, in which a fixed power supply voltage VP is applied to the gate terminal of the TFT 19 for non-display data writing. When a selection voltage is applied to one of scanning signal lines G1 to Gn, a TFT 18 for writing is turned on and a display data voltage to turn off the TFT 19 for non-display data writing is applied to data signal lines D1 to Dm. In a partial display mode, while a non-selection voltage is applied to all the scanning signal lines G1 to Gn, a non-display data voltage to turn on the TFT 19 for non-display data writing is applied to the data signal lines D1 to Dm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a display device, and more particularly to a display device having a partial display function.

  In the display device, in order to reduce power consumption, an image may be displayed only in a necessary part (hereinafter referred to as a display area) in the screen, and a partial display in which an image is not displayed in other parts may be performed. . Partial display is also called partial drive. In the liquid crystal display device, partial display can be performed by writing non-display data (for example, black data) to a pixel circuit outside the display area, and then selecting no scanning signal line outside the display area.

  However, in an organic EL display device using an organic electroluminescence (hereinafter referred to as EL) element, partial display cannot be performed correctly by the above method. The reason is as follows. In a pixel circuit of an organic EL display device, a writing TFT is provided between a gate terminal of a driving TFT (Thin Film Transistor) that controls the amount of current flowing through the organic EL element and a data signal line. Even if the writing TFT is controlled to be in the OFF state, there is leakage current and parasitic capacitance between the source and drain, so that writing is performed on the pixel circuit in the display region to the gate terminal of the driving TFT of the pixel circuit outside the display region. Voltage (data signal line voltage) is applied. If this state continues, the driving TFT of the pixel circuit outside the display area should be turned off, but the non-display area emits light.

Therefore, in order to perform partial display on the organic EL display device, a method different from that of the liquid crystal display device is required. Specific methods are disclosed in Patent Documents 1 and 2, for example. In the patent document 1, in the partial display mode, the scanning signal line driving circuit performs scanning in the same manner as normal, and latches black data when scanning moves from the display area to the outside of the display area, and the scanning period outside the display area. Discloses a method of stopping the operation of the data signal line driving circuit. Patent Document 2 discloses a method in which a current blocking transistor is provided between a driving TFT and an organic EL element, and the current blocking transistor is turned off in the partial display mode.
JP 2003-316315 A JP 2003-122304 A

  However, in the method disclosed in Patent Document 1, since the scanning signal line driving circuit performs the same scanning in the partial display mode, the effect of reducing power consumption is small. Further, the method disclosed in Patent Document 2 requires a control line for controlling the current interrupting transistor, which increases the circuit amount.

  Therefore, an object of the present invention is to provide a display device having a partial display function and having a small circuit amount and low power consumption.

The first invention is a display device having a partial display function,
A pixel array including a plurality of pixel circuits, a plurality of scanning signal lines, and a plurality of data signal lines arranged two-dimensionally;
A scanning signal line driving circuit for driving the scanning signal line;
A data signal line driving circuit for driving the data signal line,
The pixel circuit includes:
A light emitting element;
A driving element for controlling the amount of current flowing through the light emitting element;
A first switch element provided between a control terminal of the driving element and the data signal line, the control terminal being connected to the scanning signal line;
A second switch element provided between the control terminal of the drive element and the data signal line, and having a fixed voltage applied to the control terminal;
A capacitive element that holds a voltage applied to the control terminal of the drive element,
When a selection voltage is applied to any one of the scanning signal lines, a display data voltage that turns on the first switch element and turns off the second switch element is applied to the data signal line. ,
In the partial display mode, a non-display data voltage that turns on the second switch element is applied to the data signal line while a non-selection voltage is applied to all the scanning signal lines. And

According to a second invention, in the first invention,
In the partial display mode, the non-selection voltage is fixedly applied to the scanning signal lines outside the display area.

A third invention is a display device having a partial display function,
A pixel array including a plurality of pixel circuits, a plurality of scanning signal lines, and a plurality of data signal lines arranged two-dimensionally;
A scanning signal line driving circuit for driving the scanning signal line;
A data signal line driving circuit for driving the data signal line,
The pixel circuit includes:
A light emitting element;
A driving element for controlling the amount of current flowing through the light emitting element;
A switch element provided between the control terminal of the drive element and the data signal line, the control terminal being connected to the scanning signal line;
A capacitive element that holds a voltage applied to the control terminal of the drive element,
When a selection voltage is applied to any one of the scanning signal lines, a display data voltage for turning on the switch element is applied to the data signal line,
In the partial display mode, the pixels in the display area are applied while the first non-selection voltage is applied to the scanning signal lines in the display area and the second non-selection voltage is applied to the scanning signal lines outside the display area. A non-display data voltage is applied to the data signal line so that the switch element of the circuit is turned off and the switch element of the pixel circuit outside the display region is turned on.

According to a fourth invention, in the third invention,
In the partial display mode, the second non-selection voltage is fixedly applied to the scanning signal lines outside the display area.

According to a fifth invention, in the first or third invention,
The light emitting device is an organic electroluminescence device.

  According to the first aspect, in the partial display mode, if the non-display data voltage is applied to the data signal line, the non-display data voltage can be written to the pixel circuit without selecting the scanning signal line. Power consumption can be reduced. Further, since a fixed voltage is applied to the control terminal of the second switch element, a control line for controlling the second switch element is unnecessary. Therefore, it is possible to obtain a display device that performs partial display with low power consumption without significantly increasing the circuit amount.

  According to the second aspect, in the partial display mode, the power consumption in the partial display mode can be reduced by fixing the voltage of the scanning signal line outside the display area to the non-selection voltage.

  According to the third aspect, in the partial display mode, if the non-display data voltage is applied to the data signal line, the non-display data voltage can be written to the pixel circuit outside the display region without selecting the scanning signal line. The power consumption in the partial display mode can be reduced. Further, it is not necessary to add a circuit element to the pixel circuit in order to perform partial display. Therefore, it is possible to obtain a display device that performs partial display with low power consumption without significantly increasing the circuit amount.

  According to the fourth aspect of the invention, in the partial display mode, the power consumption in the partial display mode can be reduced by fixing the voltage of the scanning signal line outside the display area to the second non-selection voltage.

  According to the fifth aspect of the present invention, an organic EL display device that performs partial display with low power consumption without significantly increasing the circuit amount can be obtained.

(First embodiment)
FIG. 1 is a diagram showing a configuration of an organic EL display device according to the first embodiment of the present invention. The organic EL display device 1 shown in FIG. 1 includes a pixel array 10, a display control circuit 11, a scanning signal line driving circuit 12, and a data signal line driving circuit 13. Hereinafter, m and n are integers of 2 or more, i is an integer of 1 to n, and j is an integer of 1 to m.

  The pixel array 10 includes (m × n) pixel circuits 14, n scanning signal lines G1 to Gn, and m data signal lines D1 to Dm. The pixel circuits 14 are arranged two-dimensionally. More specifically, (m × n) pixel circuits 14 are arranged side by side in the row direction (horizontal direction in FIG. 1) and n in the column direction (vertical direction in FIG. 1). The scanning signal lines G1 to Gn are commonly connected to the pixel circuits 14 arranged in the same row. The data signal lines D1 to Dm are commonly connected to the pixel circuits 14 arranged in the same column.

  The display control circuit 11 outputs a control signal C1 to the scanning signal line drive circuit 12, and outputs a control signal C2 and display data DT to the data signal line drive circuit 13. The scanning signal line drive circuit 12 switches and applies the selection voltage and the non-selection voltage to the scanning signal lines G1 to Gn based on the control signal C1. The data signal line driving circuit 13 applies a voltage corresponding to the display data DT (hereinafter referred to as display data voltage) to the data signal lines D1 to Dm based on the control signal C2.

  The pixel circuit 14 is obtained by adding a non-display data writing TFT 19 to a pixel circuit having a so-called 2TFT + 1C configuration. The pixel circuit 14 includes an organic EL element 15, a driving TFT 16, a capacitor 17, a writing TFT 18, and a non-display data writing TFT 19. All the three TFTs included in the pixel circuit 14 are P-channel type.

  As shown in FIG. 1, the organic EL element 15 and the driving TFT 16 are connected in series, the power supply voltage VP is applied to the source terminal of the driving TFT 16, and the common electrode voltage VCOM is applied to the cathode terminal of the organic EL element 15. The A capacitor 17 is provided between the gate terminal and the source terminal of the driving TFT 16. A writing TFT 18 is provided between the gate terminal of the driving TFT 16 and the data signal line Dj, and the gate terminal of the writing TFT 18 is connected to the scanning signal line Gi. A non-display data writing TFT 19 is further provided between the gate terminal of the driving TFT 16 and the data signal line Dj, and a fixed power supply voltage VP is applied to the gate terminal of the non-display data writing TFT 19.

  The organic EL element 15 is a light emitting element that emits light with a luminance corresponding to the amount of flowing current. The driving TFT 16 is a driving element that controls the amount of current flowing through the organic EL element 15 according to the gate terminal voltage. The capacitor 17 is a capacitive element that holds the gate terminal voltage of the driving TFT 16. The writing TFT 18 and the non-display data writing TFT 19 operate independently of each other and switch whether to apply the voltage of the data signal line Dj to the gate terminal of the driving TFT 16.

  The organic EL display device 1 has a partial display function, and displays an image on the entire screen in the normal display mode, and displays an image on a part (display area) of the screen in the partial display mode. Hereinafter, the first to kth lines (k is an integer of 1 to less than n) on the screen are assumed to be display areas in the partial display mode. The display control circuit 11 is supplied with a mode control signal MC indicating the normal display mode or the partial display mode. The display control circuit 11 outputs different control signals C1 and C2 according to the mode control signal MC. The scanning signal line drive circuit 12 and the data signal line drive circuit 13 perform different operations according to the mode control signal MC.

  FIG. 2 is a signal waveform diagram in the normal display mode of the organic EL display device 1. FIG. 3 is a signal waveform diagram of the partial display mode of the organic EL display device 1. Hereinafter, it is assumed that the power supply voltage VP is 10 V, the threshold voltage Vth of the non-display data writing TFT 19 is −2 V, and the display data voltage range is 0 to 10 V. The display data voltage of 0V is a voltage for performing white display (white data voltage), and the display data voltage of 10V is a voltage for performing black display (black data voltage). In the partial display mode, a voltage to be written to the pixel circuit 14 outside the display area (hereinafter referred to as a non-display data voltage) is set to 14 V higher than the black data voltage.

  In the normal display mode (FIG. 2), the scanning signal line drive circuit 12 sequentially selects one scanning signal line from the scanning signal lines G1 to Gn, and −4V is selected as the selection voltage for the selected scanning signal line. 14 V is applied as a non-selection voltage to the other scanning signal lines. The data signal line driving circuit 13 applies a display data voltage (0 to 10 V) to the data signal lines D1 to Dm.

  In the pixel circuit 14, when the voltage of the scanning signal line Gi becomes the selection voltage, the gate terminal voltage of the writing TFT 18 is −4 V, the source terminal voltage is 0 to 10 V, and the writing TFT 18 is turned on. For this reason, the voltage of the data signal line Dj (display data voltage) is applied to the gate terminal of the driving TFT 16, and the capacitor 17 stores an amount of charge corresponding to the difference between the power supply voltage VP and the display data voltage. In this way, the display data voltage is written into the pixel circuit 14 via the writing TFT 18.

  Thereafter, when the voltage of the scanning signal line Gi becomes a non-selection voltage, the gate terminal voltage of the writing TFT 18 becomes 14V, and the writing TFT 18 is turned off. Even after the writing TFT 18 is turned off, the gate terminal voltage of the driving TFT 16 is maintained at the previous level by the action of the capacitor 17. Accordingly, until the voltage of the scanning signal line Gi becomes the selection voltage again, the organic EL element 15 emits light with a luminance corresponding to the display data voltage (gate terminal voltage of the driving TFT 16) written in the pixel circuit 14.

  Since the gate terminal voltage of the non-display data writing TFT 19 is fixed to 10V, even if the voltage of the data signal line Dj changes in the range of 0 to 10V, the non-display data writing TFT 19 is connected between the gate and the source. The voltage Vgs is always 0 V or higher, and the non-display data writing TFT 19 remains off. Therefore, in the normal display mode, the non-display data writing TFT 19 can be ignored.

  In the partial display mode (FIG. 3), the scanning signal line drive circuit 12 sequentially selects one scanning signal line from the scanning signal lines G1 to Gk in the display area, and the selected scanning signal line has a selection voltage. -4V is applied, and other scanning signal lines (including scanning signal lines Gk + 1 to Gn outside the display area) are applied with 14V as a non-selection voltage. The data signal line driving circuit 13 applies the display data voltage (0 to 10 V) to the data signal lines D1 to Dm when the selection voltage is applied to any of the scanning signal lines G1 to Gk, and otherwise. When the non-selection voltage is applied to all the scanning signal lines G1 to Gn, the non-display data voltage (14V) is applied to the data signal lines D1 to Dm.

  In the pixel circuit 14 in the display area, when the voltage of the scanning signal line Gi becomes the selection voltage, the display data voltage is written, and thereafter, the organic EL element 15 emits light with luminance according to the written display data voltage.

  Since the gate terminal voltage of the non-display data writing TFT 19 is fixed at 10 V, when the voltages of the data signal lines D1 to Dm become the non-display data voltage, all the pixel circuits 14 (in the display area or outside the display area). , The source terminal voltage of the non-display data writing TFT 19 is 14 V, the gate-source voltage Vgs is −4 V, and the non-display data writing TFT 19 is turned on. For this reason, the voltage of the data signal line Dj (non-display data voltage) is applied to the gate terminal of the driving TFT 16, and the capacitor 17 stores an amount of charge corresponding to the difference between the power supply voltage VP and the non-display data voltage. The In this way, the non-display data voltage is written into the pixel circuit 14 via the non-display data writing TFT 19.

  When a non-display data voltage is applied to the data signal lines D1 to Dm in the partial display mode, the non-display data voltage is written not only to the pixel circuit 14 outside the display area but also to the pixel circuit 14 inside the display area. Therefore, in order to perform partial display, it is necessary to write the display data voltage to the pixel circuit 14 in the display area in a cycle in which flicker does not occur.

  As described above, in the organic EL display device 1, when the selection voltage (−4V) is applied to any of the scanning signal lines G1 to Gn, the writing TFT 18 is turned on, and the non-display data writing TFT 19 is turned on. The display data voltage (0 to 10 V) that turns off is applied to the data signal lines D1 to Dm. In the partial display mode, the non-display data voltage (14V) that turns on the non-display data writing TFT 19 while the non-selection voltage (14V) is applied to all of the scanning signal lines G1 to Gn is the data. Applied to the signal lines D1 to Dm.

  Thus, in the partial display mode, if the non-display data voltage is applied to the data signal lines D1 to Dm, the non-display data voltage can be written to the pixel circuit 14 without selecting the scanning signal lines G1 to Gn. . In particular, in the partial display mode, the voltages of the scanning signal lines Gk + 1 to Gn outside the display area may be fixed to the non-selection voltage. Thereby, power consumption in the partial display mode can be reduced.

  Further, in order to perform partial display, a non-display data writing TFT 19 is added to the pixel circuit 14. However, since a fixed power supply voltage VP is applied to the gate terminal of the non-display data writing TFT 19, A control line for controlling the display data writing TFT 19 is not necessary. Therefore, according to the organic EL display device 1, partial display can be performed with low power consumption without significantly increasing the circuit amount and without significantly reducing the aperture ratio of the pixel.

  In the example shown in FIG. 3, the data signal line drive circuit 13 does not display on the data signal lines D1 to Dm when a non-selection voltage is applied to all of the scanning signal lines G1 to Gn in the partial display mode. Although the data voltage is applied, the period during which the non-display data voltage is applied may be shorter. For example, the data signal line driving circuit 13 applies the non-display data voltage to the data signal lines D1 to Dm during a part of the period in which the non-selection voltage is applied to all of the scanning signal lines G1 to Gn in the partial display mode. May be. Further, the data signal line driving circuit 13 may apply the non-display data voltage within all the frame times, or may apply the non-display data within a part of the frame time. As described above, in the partial display mode, the non-display data voltage that turns on the non-display data writing TFT 19 is applied to the data signal lines D1 to D1 while the non-selection voltage is applied to all of the scanning signal lines G1 to Gn. It may be applied to Dm.

(Second Embodiment)
FIG. 4 is a diagram showing a configuration of an organic EL display device according to the second embodiment of the present invention. The organic EL display device 2 shown in FIG. 4 includes a pixel array 20, a display control circuit 11, a scanning signal line driving circuit 22, and a data signal line driving circuit 13. Among the constituent elements of the present embodiment, the same elements as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  The pixel array 20 includes (m × n) pixel circuits 24, n scanning signal lines G1 to Gn, and m data signal lines D1 to Dm. The configuration of the pixel array 20 is the same as that of the pixel array 10 according to the first embodiment. The pixel circuit 24 is a pixel circuit having a so-called 2TFT + 1C configuration. The configuration of the pixel circuit 24 is the same as that of the pixel circuit 14 according to the first embodiment, except that the non-display data writing TFT 19 is not included.

  Similar to the first embodiment, the organic EL display device 2 displays an image on the entire screen in the normal display mode, and displays an image in a predetermined display area in the partial display mode. FIG. 5 is a signal waveform diagram in the normal display mode of the organic EL display device 2. FIG. 6 is a signal waveform diagram of the partial display mode of the organic EL display device 2. In the organic EL display device 2 as well, as in the first embodiment, the power supply voltage VP is 10 V, the display data voltage range is 0 to 10 V, and the non-display data voltage is set to 14 V.

  In the normal display mode (FIG. 5), the scanning signal line drive circuit 22 sequentially selects one scanning signal line from the scanning signal lines G1 to Gn, and −4V is selected as the selection voltage for the selected scanning signal line. 10 V (different from the first embodiment) is applied as a non-selection voltage to the other scanning signal lines. The data signal line driving circuit 13 applies a display data voltage (0 to 10 V) to the data signal lines D1 to Dm. The operation in the normal display mode is the same as that in the first embodiment except that the non-selection voltage is 10V.

  In the partial display mode (FIG. 6), the scanning signal line drive circuit 22 sequentially selects one scanning signal line from the scanning signal lines G1 to Gk in the display area, and the selected scanning signal line has a selection voltage. As a non-selection voltage, 10V (different from the first embodiment) is applied to the other scanning signal lines (including the scanning signal lines Gk + 1 to Gn outside the display area). The data signal line driving circuit 13 applies the display data voltage (0 to 10 V) to the data signal lines D1 to Dm when the selection voltage is applied to any of the scanning signal lines G1 to Gk, and otherwise. When the non-selection voltage is applied to all the scanning signal lines G1 to Gn, the non-display data voltage (14V) is applied to the data signal lines D1 to Dm.

  When the non-display data voltage is applied to the data signal lines D1 to Dm, the scanning signal line drive circuit 22 applies 14V as the non-selection voltage to the scanning signal lines G1 to Gk in the display area, and the outside of the display area. Next, 10 V is applied as a non-selection voltage to the scanning signal lines Gk + 1 to Gn. In the partial display mode, a non-selection voltage of 10 V is always applied to the scanning signal lines Gk + 1 to Gn outside the display area.

  In the pixel circuit 24 outside the display area, when the voltage of the data signal line Dj becomes a non-display data voltage, the gate terminal voltage of the writing TFT 18 is 10 V, the source terminal voltage is 14 V, and the gate-source voltage Vgs is −4 V. The writing TFT 18 is turned on. For this reason, the voltage of the data signal line Dj (non-display data voltage) is applied to the gate terminal of the driving TFT 16, and the capacitor 17 stores an amount of charge corresponding to the difference between the power supply voltage VP and the non-display data voltage. The In this way, the non-display data voltage is written to the pixel circuit 24 outside the display area via the write TFT 18.

  On the other hand, in the pixel circuit 24 in the display area, when the voltage of the data signal lines D1 to Dm becomes the non-display data voltage, the gate terminal voltage and the source terminal voltage of the writing TFT 18 are both 14V, and between the gate and the source. The voltage Vgs becomes 0 V, and the writing TFT 18 remains off. For this reason, the non-display data voltage is not written to the pixel circuit 24 in the display area.

  As described above, in the organic EL display device 2, when the selection voltage (−4 V) is applied to any of the scanning signal lines G <b> 1 to Gn, the display data voltage (0 to 0) that turns on the writing TFT 18. 10V) is applied to the data signal lines D1 to Dm. In the partial display mode, a non-selection voltage of 14 V is applied to the scanning signal lines G1 to Gk in the display area, and a non-selection voltage of 10 V is applied to the scanning signal lines Gk + 1 to Gn outside the display area. The non-display data voltage (14V) that turns on the writing TFT 18 of the pixel circuit 24 in the display area and turns on the writing TFT 18 of the pixel circuit 24 outside the display area is applied to the data signal lines D1 to Dm. The

  As described above, in the partial display mode, if the non-display data voltage is applied to the data signal lines D1 to Dm, the non-display data voltage is applied to the pixel circuit 24 in the display area without selecting the scanning signal lines G1 to Gn. Can write. In particular, in the partial display mode, the voltage of the scanning signal lines Gk + 1 to Gn outside the display area may be fixed to a non-selection voltage of 10V. Thereby, power consumption in the partial display mode can be reduced.

  In the partial display mode, the non-selection voltage applied to the scanning signal lines G1 to Gk in the display area is switched between 10V and 14V, but the non-selection voltage applied to the scanning signal lines Gk + 1 to Gn outside the display area. Is fixed at 10V. In a normal usage mode, the display area in the partial display mode is sufficiently smaller than the non-display area (the part excluding the display area from the entire screen). Therefore, in the normal usage mode, the power consumption in the partial display mode is smaller than the power consumption in the normal display mode.

  Further, it is not necessary to add a circuit element to the pixel circuit 24 in order to perform partial display. Therefore, according to the organic EL display device 2, it is possible to perform partial display with low power consumption without significantly increasing the circuit amount and without greatly reducing the aperture ratio of the pixel.

  In the organic EL display device 2, as in the first embodiment, the period during which the data signal line driving circuit 13 applies the non-display data voltage to the data signal lines D1 to Dm is shorter than the example shown in FIG. Also good.

  In addition, an organic EL display device has been described as an example of a display device having a partial display function so far, but a display device other than the organic EL display device has a partial display function in the same manner, and has a circuit amount and consumption. A display device with low power can be configured.

It is a figure which shows the structure of the organic electroluminescence display which concerns on the 1st Embodiment of this invention. FIG. 2 is a signal waveform diagram in a normal display mode of the organic EL display device shown in FIG. 1. FIG. 2 is a signal waveform diagram in a partial display mode of the organic EL display device shown in FIG. 1. It is a figure which shows the structure of the organic electroluminescence display which concerns on the 2nd Embodiment of this invention. FIG. 5 is a signal waveform diagram in a normal display mode of the organic EL display device shown in FIG. 4. FIG. 5 is a signal waveform diagram in a partial display mode of the organic EL display device shown in FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 ... Organic EL display device 10, 20 ... Pixel array 11 ... Display control circuit 12, 22 ... Scanning signal line drive circuit 13 ... Data signal line drive circuit 14, 24 ... Pixel circuit 15 ... Organic EL element 16 ... For drive TFT
17 ... Capacitor 18 ... TFT for writing
19 ... Non-display data writing TFT

Claims (5)

A display device having a partial display function,
A pixel array including a plurality of pixel circuits, a plurality of scanning signal lines, and a plurality of data signal lines arranged two-dimensionally;
A scanning signal line driving circuit for driving the scanning signal line;
A data signal line driving circuit for driving the data signal line,
The pixel circuit includes:
A light emitting element;
A driving element for controlling the amount of current flowing through the light emitting element;
A first switch element provided between a control terminal of the driving element and the data signal line, the control terminal being connected to the scanning signal line;
A second switch element provided between the control terminal of the drive element and the data signal line, and having a fixed voltage applied to the control terminal;
A capacitive element that holds a voltage applied to the control terminal of the drive element,
When a selection voltage is applied to any one of the scanning signal lines, a display data voltage that turns on the first switch element and turns off the second switch element is applied to the data signal line. ,
In the partial display mode, a non-display data voltage that turns on the second switch element is applied to the data signal line while a non-selection voltage is applied to all the scanning signal lines. A display device.   The display device according to claim 1, wherein in the partial display mode, the non-selection voltage is fixedly applied to the scanning signal lines outside the display area. A display device having a partial display function,
A pixel array including a plurality of pixel circuits, a plurality of scanning signal lines, and a plurality of data signal lines arranged two-dimensionally;
A scanning signal line driving circuit for driving the scanning signal line;
A data signal line driving circuit for driving the data signal line,
The pixel circuit includes:
A light emitting element;
A driving element for controlling the amount of current flowing through the light emitting element;
A switch element provided between the control terminal of the drive element and the data signal line, the control terminal being connected to the scanning signal line;
A capacitive element that holds a voltage applied to the control terminal of the drive element,
When a selection voltage is applied to any one of the scanning signal lines, a display data voltage for turning on the switch element is applied to the data signal line,
In the partial display mode, the pixels in the display area are applied while the first non-selection voltage is applied to the scanning signal lines in the display area and the second non-selection voltage is applied to the scanning signal lines outside the display area. A display device, wherein a non-display data voltage is applied to the data signal line so that a switch element of a circuit is turned off and a switch element of a pixel circuit outside a display region is turned on.   The display device according to claim 3, wherein in the partial display mode, the second non-selection voltage is fixedly applied to the scanning signal lines outside the display area.   The display device according to claim 1, wherein the light emitting element is an organic electroluminescence element.