JP2008015401A - Electro-optic device, method for driving electro-optic device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optic device that enables the power consumption thereof to be reduced, a method for driving an electro-optic device, and an electronic apparatus. <P>SOLUTION: The electro-optic device 1 can select a full screen display mode that renders the entire region of a display screen A into a display region or a partial display mode that renders a part of the entire region of the display screen A into a display region while rendering the other region into a nondisplay region. The electro-optic device 1 is equipped with: a scanning line drive circuit 10 sequentially supplying a selection voltage to select a scanning line Y to a plurality of scanning lines Y; a data line drive circuit 20 supplying an image signal to a plurality of data lines X when the scanning line Y is selected; and an equalizer circuit 40 connecting or disconnecting the data line X and a common electrode 56. The equalizer circuit 40 connects the data line X to the common electrode 56 when a scanning line Y in the nondisplay region is selected in the plurality of scanning lines Y in the partial display mode. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electro-optical device, a driving method of the electro-optical device, and an electronic apparatus.

  Conventionally, electro-optical devices such as liquid crystal devices are known. The electro-optical device includes, for example, a plurality of scanning lines provided at predetermined intervals and a plurality of data lines provided at predetermined intervals so as to intersect the plurality of scanning lines.

Pixels are provided at intersections between the scanning lines and the data lines. The pixel includes a pixel capacitor including a pixel electrode and a common electrode, and a thin film transistor (hereinafter referred to as a TFT (Thin Film Transistor)) as a switching element. A plurality of these pixels are arranged in a matrix to form a display screen.
A scanning line is connected to the gate of the TFT, a data line is connected to the source of the TFT, and a pixel electrode is connected to the drain of the TFT.

  The scanning line driving circuit supplies a selection voltage for selecting a scanning line to each scanning line in a predetermined order. When a selection voltage is supplied to the scanning line, all TFTs connected to the scanning line are turned on.

  The data line driving circuit supplies an image signal to each data line, and writes an image voltage based on the image signal to the pixel electrode via the TFT in the on state.

The above electro-optical device operates as follows.
That is, by sequentially supplying the selection voltage to the scanning line, all the TFTs connected to the certain scanning line are turned on, and all the pixels related to the scanning line are selected. Then, an image signal is supplied to the data line in synchronization with the selection of these pixels. Then, an image signal is supplied to all the selected pixels via the on-state TFTs, and an image voltage based on the image signal is written to the pixel electrode.

  When an image voltage is written to the pixel electrode, a driving voltage is applied to the liquid crystal due to a potential difference between the pixel electrode and the common electrode. When a driving voltage is applied to the liquid crystal, the alignment and order of the liquid crystal change, the light transmitted through the liquid crystal changes, and gradation display is performed.

  Such an electro-optical device is required to reduce power consumption. Therefore, instead of displaying on the entire surface of the display screen as described above (hereinafter, this case is referred to as a full screen display mode), it is displayed only on a part of the display screen (hereinafter, this case is a partial display). (Referred to as Patent Mode 1).

  In the electro-optical device disclosed in Patent Document 1, in the partial display mode, the display screen is divided into a display area and a non-display area. In the display area, an image voltage corresponding to an image such as a remaining battery level or a time display is written in each pixel electrode, and gradation display is performed from each pixel. On the other hand, in the non-display area, an image voltage corresponding to an off display image such as a white image for normally white and a black image for normally black is written to each pixel electrode, and gradation display is performed from each pixel.

Here, in the partial display mode, an image voltage corresponding to a certain image that is an off-display image is written to the pixel electrode in the non-display area, so the cycle is slower than the period in which the image voltage is written to the pixel electrode in the display area. Even when the image voltage is written, display deterioration is not noticeable. Therefore, in the partial display mode, the period of writing the image voltage to the pixel electrode in the non-display area can be delayed compared to the period of writing the image voltage to the pixel electrode in the display area, thereby reducing power consumption.
JP 2001-356746 A

  However, the electro-optical device as described above is required to further reduce power consumption. In the above-described electro-optical device, even in the partial display mode, even if the cycle of writing the image voltage to the pixel electrode in the non-display area is delayed, the image voltage is written at every predetermined cycle, so that the power consumption is sufficient. May not be reduced.

  SUMMARY An advantage of some aspects of the invention is that it provides an electro-optical device, a driving method of the electro-optical device, and an electronic apparatus that can reduce power consumption.

  The electro-optical device of the present invention includes a plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to intersections of the plurality of scanning lines and the plurality of data lines, and the pixel electrodes. A full-screen display mode in which the entire screen is a display area, a part of the entire screen is a display area, and another area is a non-display area The partial display mode is an electro-optical device that can be selected, a scanning line driving circuit that sequentially supplies a selection voltage for selecting the scanning line to the plurality of scanning lines, and when the scanning line is selected. A data line driving circuit for supplying an image signal to the plurality of data lines; and an equalizer circuit having a plurality of switch elements connecting the plurality of data lines and the common electrode, wherein the equalizer circuit includes the partial display. In mode When the scanning lines of the display area is selected, characterized by connecting the common electrode and the data line.

If the pixel electrode and the common electrode are at the same potential, no driving voltage is applied to the liquid crystal. Therefore, a white gradation is displayed for normally white, and a black gradation is displayed for normally black. .
Therefore, according to the present invention, in the partial display mode, the data line and the common electrode are connected when the scanning line in the non-display area among the plurality of scanning lines is selected. For this reason, charge movement occurs between the pixel electrode and the common electrode via the data line, and the pixel electrode and the common electrode have the same potential. Therefore, the off-display image can be displayed on the pixels in the non-display area without supplying an image signal corresponding to the off-display image to the data line by the data line driving circuit. Therefore, when a scanning line in a non-display area is selected by the scanning line driving circuit, power consumption can be reduced by not supplying an image signal to the data line by the data line driving circuit.

  The electro-optical device according to the aspect of the invention further includes a control circuit that alternately supplies a first voltage and a second voltage having a higher potential than the first voltage to the common electrode, and the data line driving circuit includes the data line driving circuit, After the first voltage is supplied to the common electrode, an image signal having a higher potential than the first voltage is supplied to the data line, and after the second voltage is supplied to the common electrode, the data line is supplied to the data line. An image signal having a potential lower than the second voltage is supplied, and the equalizer circuit is configured to select the common line before the scanning line of the display area is selected from the plurality of scanning lines in the partial display mode. When the voltage of the electrode varies from the first voltage to the second voltage or from the second voltage to the first voltage, it is preferable to connect the data line and the common electrode.

According to the present invention, in the partial display mode, before the scanning line of the display area is selected and when the voltage of the common electrode is changed from the first voltage to the second voltage or from the second voltage to the first voltage, The data line and the common electrode were connected. For this reason, charge movement occurs between the data line and the common electrode, and the data line and the common electrode have the same potential.
Therefore, when the voltage of the common electrode is increased from the first voltage to the second voltage, the above-described data line and the common electrode are changed from the voltage based on the image signal whose potential is higher than the first voltage. The voltage at the common electrode can be increased from the first voltage to the second voltage by using the electric charge when the voltage is reduced to the same potential.
When the common electrode voltage is decreased from the second voltage to the first voltage, the common electrode voltage is decreased from the second voltage to a voltage at which the data line and the common electrode have the same potential. By using the electric charge, the voltage of the data line can be increased from a voltage based on an image signal having a lower potential than the second voltage to a voltage at which the data line and the common electrode have the same potential.
As described above, even if an image signal is supplied from the data line driving circuit to the data line or a predetermined voltage is not supplied from the control circuit to the common electrode, the charge is moved between the data line and the common electrode. Since the voltage of the data line and the common electrode can be varied, the power consumption can be further reduced.

  In the electro-optical device according to the aspect of the invention, it is preferable that the data line driving circuit and the equalizer circuit are provided along two sides facing each other in the entire screen.

  According to the present invention, the data line driving circuit and the equalizer circuit are provided along two sides facing each other in the entire screen. For this reason, since the capacity of the data line, the switching element, or the like is not hung with respect to the image signal output to the data line, the delay amount in the image signal can be reduced.

An electronic apparatus according to an aspect of the invention includes the above-described electro-optical device.
According to the present invention, there are effects similar to those described above.

The driving method of the electro-optical device according to the present invention includes a plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to intersections of the plurality of scanning lines and the plurality of data lines, and the pixels A full-screen display mode that includes a common electrode provided opposite to the electrode and uses the entire screen as a display area, and a portion in which a part of the whole screen is a display area and another area is a non-display area A display mode, wherein the data line and the common electrode are connected when the scanning line of the non-display area is selected in the partial display mode. Features.
According to the present invention, there are effects similar to those described above.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of embodiments and modifications, the same constituent elements are denoted by the same reference numerals, and the description thereof is omitted or simplified.

<Embodiment>
FIG. 1 is a block diagram of an electro-optical device 1 according to an embodiment of the present invention.
The electro-optical device 1 includes a liquid crystal panel AA.

  The liquid crystal panel AA includes a display screen A, a scanning line driving circuit 10 that is provided around the display screen A and drives the pixels 50, a data line driving circuit 20, a common line driving circuit 30 as a control circuit, and an equalizer circuit 40. Is provided.

  This liquid crystal panel AA intersects 320 scanning lines Y1 to Y320 and 320 common lines Z1 to Z320 alternately provided at predetermined intervals, and these scanning lines Y1 to Y320 and common lines Z1 to Z320. And 240 columns of data lines X1 to X240. Pixels 50 are provided at the intersections of the scanning lines Y and the data lines X.

  The pixel 50 includes a TFT 51, a pixel electrode 55, a common electrode 56 provided to face the pixel electrode 55, one electrode connected to the common electrode 56 via the common line Z, and the other electrode connected to the pixel electrode 55. It is comprised by the storage capacity 53 connected to. The pixel electrode 55 and the common electrode 56 constitute a pixel capacitor 54.

  The scanning line Y is connected to the gate of the TFT 51, the data line X is connected to the source of the TFT 51, and the other electrode of the pixel electrode 55 and the storage capacitor 53 is connected to the drain of the TFT 51. Therefore, the TFT 51 is turned on when a selection voltage is applied from the scanning line Y, and the data line X and the pixel electrode 55 and the other electrode of the storage capacitor 53 are brought into conduction.

The scanning line driving circuit 10 sequentially supplies a selection voltage for turning on the TFT 51 to the plurality of scanning lines Y. For example, when a selection voltage is supplied to a certain scanning line Y, all the TFTs 51 connected to the scanning line Y are turned on, and all the pixels 50 related to the scanning line Y are selected.
This scanning line driving circuit 10 has a full screen display mode in which all areas of the display screen A are displayed areas, a part of all areas of the display screen A as display areas, and other areas are not displayed. The period when the selection voltage is sequentially supplied to the plurality of scanning lines Y is different from the partial display mode as the region.

FIG. 2 is a diagram showing the display screen A in the partial display mode.
In the partial display mode, the display screen A is divided into a display area 71 and a non-display area 72 that sandwiches the display area 71. In the display area 71, an image such as a remaining battery level and time display is displayed, and in the non-display area 72, an off display image is displayed. That is, in the non-display area 72, a white image is displayed if it is normally white, and a black image is displayed if it is normally black.

  Returning to FIG. 1, the scanning line driving circuit 10 described above applies a period F to all the scanning lines Y of the display screen A in the full screen display mode based on a display switching signal input from a display control unit (not shown). The selection voltage is supplied in sequence. On the other hand, in the partial display mode, the selection voltage is sequentially supplied to the scanning lines Y in the display area 71 with the period F, and the selection voltages are sequentially supplied to the scanning lines Y in the non-display area 72 with the period 2F. That is, the selection voltage is sequentially supplied to the scanning lines Y in the non-display area 72 at a cycle twice that of the scanning lines Y in the display area 71.

The data line driving circuit 20 supplies an image signal to the data line X, and writes an image voltage based on the image signal to the pixel electrode 55 via the TFT 51 in the on state.
Here, the data line driving circuit 20 supplies a positive image signal having a higher potential than the voltage of the common electrode 56 to the data line X, and writes an image voltage based on the positive image signal to the pixel electrode 55. Positive polarity writing and negative polarity writing in which a negative image signal having a potential lower than the voltage of the common electrode 56 is supplied to the data line X and an image voltage based on the negative polarity image signal is written to the pixel electrode 55. Are alternately performed for each horizontal line.

  The common line driving circuit 30 alternately supplies a voltage VCOML as a first voltage and a voltage VCOMH as a second voltage having a higher potential than the voltage VCOML to the common line Z.

The equalizer circuit 40 intermittently connects the data line X and the common line Z.
The equalizer circuit 40 and the data line driving circuit 20 described above are provided along two opposite sides of the display screen A. The equalizer circuit 40 corresponds to the plurality of common lines Z, A switch 41 as a plurality of switch elements is provided. A plurality of data lines X are connected to one end of the switch 41, and a common line Z corresponding to each switch 41 is connected to the other end of the switch 41. The switch 41 is turned on / off based on a voltage CP of a control signal input from a display control unit (not shown). When the switch 41 is turned on, the plurality of data lines X connected to the switch 41 in the on state and the corresponding common line Z become conductive.

The electro-optical device 1 described above operates as follows in the full screen display mode.
That is, first, either the voltage VCOML or the voltage VCOMH is selectively supplied from the common line driving circuit 30 to the common line Z.
Specifically, the voltage VCOML and the voltage VCOMH are alternately supplied to each common line Z every frame period. For example, when the voltage VCOML is supplied to the common line Zp in the p-th row (p is an integer satisfying 1 ≦ p ≦ 320) in a certain one frame period, the voltage VCOMH is applied to the common line Zp in the next one frame period. Supply. On the other hand, when the voltage VCOMH is supplied to the common line Zp in one frame period, the voltage VCOML is supplied to the common line Zp in the next one frame period.
Further, different voltages are supplied to adjacent common lines Z. For example, when the voltage VCOML is supplied to the common line Zp in one frame period, the common line Z (p−1) in the (p−1) th row and the (p + 1) th row in the same one frame period. A voltage VCOMH is supplied to the common line Z (p + 1). On the other hand, when the voltage VCOMH is supplied to the common line Zp in one frame period, the voltage VCOML is supplied to the common line Z (p−1) and the common line Z (p + 1) in the same one frame period. .

  Next, by sequentially supplying a selection voltage from the scanning line driving circuit 10 to 320 scanning lines Y1 to Y320, all the TFTs 51 connected to each scanning line Y are sequentially turned on, and each scanning line Y is turned on. All such pixels 50 are selected sequentially.

In synchronism with the selection of the pixels 50, a positive image signal and a negative image signal are transferred from the data line driving circuit 20 to the data line X according to the voltage of the common electrode 56 by one horizontal line. Supply alternately every time.
Specifically, when the voltage VCOML is supplied to the common line Zp related to the selected pixel 50 among the 320 common lines Z1 to Z320, a positive image signal is supplied to the data line X. On the other hand, when the voltage VCOMH is supplied to the common line Zp related to the selected pixel 50 among the 320 common lines Z1 to Z320, a negative image signal is supplied to the data line X.

  Then, an image signal is supplied to all the pixels 50 selected by the scanning line driving circuit 10 from the data line driving circuit 20 via the data line X and the on-state TFT 51, and an image voltage based on this image signal is applied to the pixel electrode. 55 is written. As a result, a potential difference is generated between the pixel electrode 55 and the common electrode 56, and a driving voltage is applied to the liquid crystal.

When a driving voltage is applied to the liquid crystal, the alignment and order of the liquid crystal change, and the light transmitted through the liquid crystal changes, so that gradation display is performed.
Note that the drive voltage applied to the liquid crystal is held by the storage capacitor 53 for a period that is three digits longer than the period during which the image voltage is written.

Further, the above electro-optical device 1 operates as follows with respect to the display area 71 in the partial display mode.
That is, first, the switch 41 corresponding to the common line Zp is turned on to connect the plurality of data lines X and the common line Zp. Then, the plurality of data lines X and all the common electrodes 56 related to the common line Zp are in a conductive state and have the same potential.

Next, as described above, either the voltage VCOML or the voltage VCOMH is selectively supplied from the common line driving circuit 30 to the common line Zp.
At the same time, as described above, a positive image signal or a negative image signal is supplied from the data line driving circuit 20 to the data line X.

  Next, the switch 41 corresponding to the common line Zp is turned off, the plurality of data lines X and the common line Zp are disconnected, and the selection voltage is applied from the scanning line driving circuit 10 to the scanning line Yp as described above. Supply.

Further, the above electro-optical device 1 operates as follows with respect to the non-display area 72 in the partial display mode.
That is, first, as described above, the switch 41 corresponding to the common line Zp is turned on to connect the plurality of data lines X and the common line Zp.

Next, as described above, either the voltage VCOML or the voltage VCOMH is selectively supplied from the common line driving circuit 30 to the common line Zp.
At the same time, as described above, a positive image signal or a negative image signal is supplied from the data line driving circuit 20 to the data line X.

  Next, as described above, the selection voltage is sequentially supplied from the scanning line driving circuit 10 to the scanning line Yp while the switch 41 corresponding to the common line Zp is kept on.

FIG. 3 is a timing chart at the time of positive writing to the display area 71 in the electro-optical device 1 in the partial display mode.
In FIG. 3, GATE (m) is the voltage of the scanning line Ym of the m-th row (m is an integer satisfying 1 ≦ m ≦ 320), and SOURCE (n) is the n-th column (n is The voltage of the data line Xn) is an integer satisfying 1 ≦ n ≦ 240. VCOM (m, n) is a voltage of the common electrode 56 provided in the pixel 50 in the m-th row and the n-th column provided corresponding to the intersection of the scanning line Ym in the m-th row and the data line Xn in the n-th column. It is. CP (m) is a voltage of a control signal corresponding to the common line Zm in the m-th row.

First, at time t1, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPH. Then, the switch 41 corresponding to the common line Zm is turned on, and the plurality of data lines X and all the common electrodes 56 related to the common line Zm are brought into conduction.
Then, charge transfer occurs between the common electrode 56 in the m-th row and the n-th column having the voltage VCOMH and the data line Xn having the voltage VSL. For this reason, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column gradually decreases and becomes the voltage V1 at time t2. In addition, the voltage SOURCE (n) of the data line Xn gradually increases and reaches the voltage V1 at time t2.

Next, at time t3, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPL. Then, the switch 41 corresponding to the common line Zm is turned off, and the plurality of data lines X and all the common electrodes 56 related to the common line Zm are turned off.
At the same time, the common line drive circuit 30 supplies the voltage VCOML to the common line Zm. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column connected to the common line Zm gradually decreases and becomes the voltage VCOML at time t5.
At the same time, the data line driving circuit 20 supplies an image signal of the voltage VSH to the data line Xn. Then, the voltage SOURCE (n) of the data line Xn gradually rises to the voltage VSH at time t4.

  Next, at time t6, the scanning line driving circuit 10 supplies a selection voltage to the scanning line Ym. Then, the voltage GATE (m) of the scanning line Ym gradually rises and becomes the voltage VGH at time t7. As a result, all TFTs 51 connected to the scanning line Ym are turned on, and the voltage VSH of the data line Xn is written to the pixel electrode 55 in the m-th row and the n-th column.

  Next, at time t8, the scanning line driving circuit 10 stops supplying the selection voltage to the scanning line Ym. Then, the voltage GATE (m) of the scanning line Ym gradually decreases and becomes the voltage VGL at time t9. Thereby, all the TFTs 51 connected to the scanning line Ym are turned off, and the writing of the voltage VSH of the data line Xn to the pixel electrode 55 in the m-th row and the n-th column is completed.

FIG. 4 is a timing chart at the time of negative writing to the display area 71 in the electro-optical device 1 in the partial display mode.
In the negative polarity writing of FIG. 4, the same gradation display as that of the positive polarity writing shown in FIG. 3 is performed.

  First, at time t11, similarly to the above-described time t1, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPH. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column gradually increases and becomes the voltage V2 at time t12. In addition, the voltage SOURCE (n) of the data line Xn gradually decreases and reaches the voltage V2 at time t12.

Next, at time t13, similarly to the above-described time t3, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPL.
At the same time, the common line drive circuit 30 supplies the voltage VCOMH to the common line Zm. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column connected to the common line Zm gradually increases and becomes the voltage VCOMH at time t15.
At the same time, the data line driving circuit 20 supplies an image signal of the voltage VSL to the data line Xn. Then, the voltage SOURCE (n) of the data line Xn gradually decreases and becomes the voltage VSL at time t14.

  Next, at time t <b> 16, similarly to the above-described time t <b> 6, the scanning line driving circuit 10 supplies a selection voltage to the scanning line Ym. As a result, all TFTs 51 connected to the scanning line Ym are turned on, and the voltage VSL of the data line Xn is written to the pixel electrode 55 in the m-th row and the n-th column.

  Next, at time t18, similarly to the above-described time t8, the scanning line driving circuit 10 stops supplying the selection voltage to the scanning line Ym. As a result, all the TFTs 51 connected to the scanning line Ym are turned off, and the writing of the voltage VSL of the data line Xn to the pixel electrode 55 in the m-th row and the n-th column ends.

  FIG. 5 is a timing chart at the time of positive polarity writing to the non-display area 72 in the electro-optical device 1 in the partial display mode.

  First, at time t21, similarly to the above-described time t1, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPH. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column gradually decreases and becomes the voltage V1 at time t22. In addition, the voltage SOURCE (n) of the data line Xn gradually rises to the voltage V1 at time t22.

Next, at time t22, the voltage VCOML is supplied to the common line Zm by the common line driving circuit 30 as in the above-described time t3. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column connected to the common line Zm gradually decreases and becomes the voltage VCOML at time t23.
Further, since the plurality of data lines X and all the common electrodes 56 related to the common line Zm are conductive, the voltage SOURCE (n) of the data line Xn is equal to the voltage VCOM ( Similarly to m, n), the voltage gradually decreases and reaches the voltage VCOML at time t23.

  Next, at time t24, the selection voltage is supplied to the scanning line Ym by the scanning line driving circuit 10, similarly to the above-described time t6. As a result, all TFTs 51 connected to the scanning line Ym are turned on, and the voltage VCOML of the data line Xn is written to the pixel electrode 55 in the m-th row and the n-th column.

  Next, at time t26, similarly to the above-described time t8, the scanning line driving circuit 10 stops supplying the selection voltage to the scanning line Ym. As a result, all the TFTs 51 connected to the scanning line Ym are turned off, and the writing of the voltage VCOML of the data line Xn to the pixel electrode 55 in the m-th row and the n-th column ends.

FIG. 6 is a timing chart at the time of negative writing for the non-display area 72 in the electro-optical device 1 in the partial display mode.
In the negative polarity writing of FIG. 6, gradation display corresponding to the same off-display image as in the positive polarity writing shown in FIG. 5 is performed.

  First, at time t31, similarly to the above-described time t11, the voltage CP (m) of the control signal corresponding to the common line Zm is set to the voltage VCPH. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column gradually increases and becomes the voltage V2 at time t32. In addition, the voltage SOURCE (n) of the data line Xn gradually decreases and reaches the voltage V2 at time t32.

Next, at time t32, the voltage VCOMH is supplied to the common line Zm by the common line driving circuit 30 as in the above-described time t13. Then, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column connected to the common line Zm gradually increases and becomes the voltage VCOMH at time t33.
Further, since the plurality of data lines X and all the common electrodes 56 related to the common line Zm are conductive, the voltage SOURCE (n) of the data line Xn is equal to the voltage VCOM ( Similarly to m, n), the voltage gradually increases and reaches the voltage VCOMH at time t33.

  Next, at the time t34, the selection voltage is supplied to the scanning line Ym by the scanning line driving circuit 10 similarly to the above-described time t16. As a result, all TFTs 51 connected to the scanning line Ym are turned on, and the voltage VCOMH of the data line Xn is written to the pixel electrode 55 in the m-th row and the n-th column.

  Next, at time t <b> 36, similarly to the above-described time t <b> 18, the scanning line driving circuit 10 stops supplying the selection voltage to the scanning line Ym. As a result, all the TFTs 51 connected to the scanning line Ym are turned off, and the writing of the voltage VCOMH of the data line Xn to the pixel electrode 55 in the m-th row and the n-th column ends.

According to this embodiment, there are the following effects.
(1) In the partial display mode, when the scanning line Ym of the non-display area 72 among the plurality of scanning lines Y is selected, the data line X and the common electrode 56 related to the common line Zm are connected. For this reason, charge movement occurs between the pixel electrode 55 and the common electrode 56 related to the common line Zm via the data line X, and the pixel electrode 55 and the common electrode 56 related to the common line Zm have the same potential. Become. Therefore, the off-display image can be displayed on the pixels 50 in the non-display area 72 without supplying the image signal corresponding to the off-display image to the data line X by the data line driving circuit 20. Therefore, when the scanning line Ym in the non-display area 72 is selected by the scanning line driving circuit 10, power consumption can be reduced by not supplying an image signal to the data line X by the data line driving circuit 20.

(2) In the partial display mode, the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column is changed from the voltage VCOML to the voltage VCOMH or the voltage VCOMH before the scanning line Ym in the display area 71 is selected. When the voltage VCOML was changed, the data line Xn and the common electrode 56 in the m-th row and the n-th column were connected. For this reason, charge transfer occurs between the data line Xn and the common electrode 56 in the m-th row and the n-th column, and both the data line Xn and the common electrode 56 in the m-th row and the n-th column have the voltage V1 or The voltage is V2.
Therefore, as shown in FIG. 3, when the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column is lowered from the voltage VCOMH to the voltage VCOML, the common electrode 56 in the m-th row and the n-th column. The voltage SOURCE (n) of the data line Xn can be raised from the voltage VSL to the voltage V1 by using the charge when the voltage VCOM (m, n) of the current drops from the voltage VCOMH to the voltage V1.
As shown in FIG. 4, when the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column is increased from the voltage VCOML to the voltage VCOMH, the voltage SOURCE (n) of the data line Xn is used. Can be increased from the voltage VCOML to the voltage V2 by using the electric charge when the voltage VSH decreases from the voltage VSH to the voltage V2.
As described above, the data line Xn and the m rows n can be supplied without supplying an image signal from the data line driving circuit 20 to the data line Xn or supplying a predetermined voltage from the common line driving circuit 30 to the common line Zm. The charge is moved between the common electrode 56 in the column and the voltage SOURCE (n) of the data line Xn and the voltage VCOM (m, n) of the common electrode 56 in the m-th row and the n-th column are changed. Therefore, power consumption can be further reduced.

  (3) The data line driving circuit 20 and the equalizer circuit 40 are provided along two opposing sides of the display screen A, respectively. For this reason, the capacity of the data line X, the TFT 51, etc. is not hung with respect to the image signal output to the data line X, so that the delay amount in the image signal can be reduced.

<Modification>
In addition, this invention is not limited to the above-mentioned embodiment, The deformation | transformation in the range which can achieve the objective of this invention, improvement, etc. are included in this invention.
For example, in the above-described embodiment, 320 scanning lines Y and 240 data lines X are provided. However, the present invention is not limited to this. For example, 480 scanning lines Y and 640 columns of data are provided. Line X may be provided.

  Further, in the above-described embodiment, the selection voltage is sequentially supplied to the scanning lines Y in the non-display area 72 at a cycle twice that of the scanning lines Y in the display area 71. The selection voltage may be sequentially supplied with a double cycle.

  In the above-described embodiment, the present invention is applied to the electro-optical device 1 using liquid crystal. However, the present invention is not limited to this and can be applied to an electro-optical device using an electro-optical material other than liquid crystal. An electro-optical material is a material whose optical characteristics such as transmittance and luminance change when an electric signal (current signal or voltage signal) is supplied. For example, a display panel using an OLED element such as an organic EL (Electro-Luminescent) or a light emitting polymer as an electro-optical material, or a microcapsule containing a colored liquid and white particles dispersed in the liquid is used as the electro-optical material. The electrophoretic display panel used as a twist ball display panel using a twist ball painted differently for each region of different polarity as an electro-optical material, a toner display panel using black toner as an electro-optical material, or The present invention can also be applied to various electro-optical devices such as a plasma display panel using a high-pressure gas such as helium or neon as an electro-optical material.

<Application example>
Next, an electronic apparatus to which the electro-optical device 1 according to the above-described embodiment is applied will be described.
FIG. 7 is a perspective view showing a configuration of a mobile phone to which the electro-optical device 1 is applied. The cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the electro-optical device 1. By operating the scroll button 3002, the screen displayed on the electro-optical device 1 is scrolled.

  The electronic apparatus to which the electro-optical device 1 is applied is not limited to the one shown in FIG. 7, but a personal computer, a portable information terminal, a digital still camera, a liquid crystal television, a viewfinder type, a monitor direct view type video tape recorder, a car navigation system. Examples of the apparatus include a device, a pager, an electronic notebook, a calculator, a word processor, a workstation, a video phone, a POS terminal, and a touch panel. And the liquid crystal device mentioned above is applicable as a display part of these various electronic devices.

1 is a block diagram of an electro-optical device according to an embodiment of the invention. FIG. FIG. 4 is a diagram illustrating a display screen in a partial display mode of the electro-optical device. 6 is a timing chart at the time of positive writing with respect to a display area in the electro-optical device in a partial display mode. 6 is a timing chart at the time of negative writing with respect to a display region in the electro-optical device in a partial display mode. 6 is a timing chart at the time of positive polarity writing to a non-display area in the electro-optical device in a partial display mode. 6 is a timing chart at the time of negative writing with respect to a non-display area in the electro-optical device in a partial display mode. It is a perspective view which shows the structure of the mobile telephone to which the electro-optical device mentioned above is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electro-optical device, 10 ... Scanning line drive circuit, 20 ... Data line drive circuit, 30 ... Common line drive circuit (control circuit), 40 ... Equalizer circuit, 50 ... Pixel, 55 ... Pixel electrode, 56 ... Common electrode, 71 ... display area, 72 ... non-display area, 3000 ... mobile phone (electronic device), A ... display screen, X ... data line, Y ... scanning line.

Claims (5)

A plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to intersections of the plurality of scanning lines and the plurality of data lines, and a common provided to face the pixel electrodes Selectable from a full-screen display mode with the entire screen as a display area and a partial display mode with a part of the full screen as a display area and the other area as a non-display area An electro-optical device,
A scanning line driving circuit for sequentially supplying a selection voltage for selecting the scanning line to the plurality of scanning lines;
A data line driving circuit for supplying an image signal to the plurality of data lines when the scanning line is selected;
An equalizer circuit having a plurality of switch elements connecting the plurality of data lines and the common electrode;
The electro-optical device, wherein the equalizer circuit connects the data line and the common electrode when a scanning line in the non-display area is selected in the partial display mode. The electro-optical device according to claim 1.
A control circuit that alternately supplies a first voltage and a second voltage having a higher potential than the first voltage to the common electrode;
The data line driving circuit includes:
After the first voltage is supplied to the common electrode, an image signal having a higher potential than the first voltage is supplied to the data line,
After the second voltage is supplied to the common electrode, an image signal having a lower potential than the second voltage is supplied to the data line,
In the partial display mode, the equalizer circuit is configured so that the voltage of the common electrode is changed from the first voltage to the second voltage or before the scanning line of the display region is selected from the plurality of scanning lines. An electro-optical device, wherein the data line and the common electrode are connected when changing from a second voltage to the first voltage. The electro-optical device according to claim 1,
The electro-optical device, wherein the data line driving circuit and the equalizer circuit are provided along two opposite sides of the entire screen.   An electronic apparatus comprising the electro-optical device according to claim 1. A plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to intersections of the plurality of scanning lines and the plurality of data lines, and a common electrode provided to face the pixel electrodes. And an electro-optical device capable of selecting a full-screen display mode in which a full screen is a display area and a partial display mode in which a part of the full screen is a display area and another area is a non-display area Driving method,
In the partial display mode, when the scanning line in the non-display area is selected, the data line and the common electrode are connected to each other.

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