JP2007178525A - Driving method of electrooptical apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrooptical apparatus with which color irregularity can be reduced by preventing the write deficiency of a pixel electrode in common inversion driving. <P>SOLUTION: The electrooptical apparatus includes a data line driving circuit and alternately performs positive polarity writing and negative polarity writing. The data line driving circuit has six output terminals OT1 to OT6 for one input terminal IT and includes a plurality of demultiplexer unit circuits for sorting an image signal supplied as a time sharing signal to six data lines X1 to X6 by connecting the output terminal OT selected from among the plurality of the output terminals OT1 to OT6 to the input terminal. Among the plurality of the data lines X1 to X6, the data line selected first after being subjected to voltage inversion in the common electrode is determined as data line X1. The demultiplexer unit circuit selects only the data line X1 in a first period 2T and successively selects the remaining data line X2 to X6 other than the data line X1 in a second period T. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for driving an electro-optical device such as a liquid crystal display device.

Conventionally, an active matrix liquid crystal display device is known as an electro-optical device. The active matrix liquid crystal display device includes a plurality of scanning lines and common lines, a plurality of data lines substantially orthogonal to the scanning lines and the common lines, and a plurality of scanning lines and data lines provided corresponding to the intersections of the scanning lines and the data lines. A first substrate having the pixel circuit, a second substrate provided opposite to the first substrate, and an electro-optic material provided between the first substrate and the second substrate. And a certain liquid crystal.
Further, the first substrate is provided with a scanning line driving circuit for driving the scanning lines and a data line driving circuit for driving the data lines.

Here, the data line driving circuit includes, for example, a plurality of demultiplexer unit circuits (see Patent Document 1). Each demultiplexer unit circuit has one input terminal and a plurality of output terminals, and the plurality of output terminals are sequentially selected by the switching element and connected to the input terminals. Thereby, the demultiplexer unit circuit distributes the image signal supplied as a time division signal from the signal source to the data line.
According to the data line driving circuit including such a demultiplexer unit circuit, the number of signal lines from the signal source to the liquid crystal panel can be greatly reduced, and the manufacturing cost of the liquid crystal display device can be reduced.

On the other hand, in the above liquid crystal display device, in order to prevent the deterioration of the liquid crystal, the polarity of the voltage applied to the liquid crystal is reversed at a constant period. Specific driving methods include, for example, frame inversion driving for switching the polarity of the liquid crystal applied voltage to the pixel electrode for each frame, and the polarity of the liquid crystal applied voltage to the pixel electrode for each horizontal line or a plurality of horizontal lines. Known are the H-line inversion driving and the HV inversion driving for switching the polarity of the liquid crystal application voltage to the pixel electrode in units of pixels.

However, in these driving methods, the common electrode is set as a fixed potential, and the potential of the pixel electrode is set so that a constant potential difference is generated between the positive side and the negative side with respect to the fixed potential. For this reason, the writing voltage of the pixel electrode requires a dynamic range twice as large as the certain potential difference, which increases power consumption.

Therefore, in addition to H line inversion driving, a driving method has been proposed in which the polarity of the voltage of the common electrode is also inverted at least for each horizontal line (hereinafter referred to as H / common inversion driving). This H /
According to the common inversion driving, the dynamic range of the output of the data line driving circuit is reduced,
Power consumption can be reduced.
In the following description, the common inversion driving means the above-mentioned H / common inversion driving,
It is assumed that common driving is performed in which only the polarity of the voltage of the common electrode is inverted without inverting the polarity of the voltage of the pixel electrode.
Japanese Patent Laid-Open No. 6-138851

By the way, in a liquid crystal display device including a plurality of demultiplexer unit circuits as in Patent Document 1, when common inversion driving is performed, the first one that is selected after the polarity of the common electrode is inverted among the plurality of data lines. The potential fluctuates due to capacitive coupling with the common line. for that reason,
After reversing the voltage polarity of the common electrode, the pixel electrode to which image data is first written is much lower than the required voltage compared to the other pixel electrodes, resulting in color There may be unevenness.

SUMMARY An advantage of some aspects of the invention is that it provides a driving method of an electro-optical device that can prevent pixel electrode writing shortage in common inversion driving and reduce color unevenness.

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 the intersections of the scanning lines and the data lines, and a plurality of pixel electrodes opposed to the pixel electrodes. An electro-optical device comprising: a common electrode; and a plurality of switching elements that bring the data line and the pixel electrode into a conductive state or a non-conductive state based on a voltage applied to the scanning line,
A scanning line driving circuit for supplying a voltage for sequentially selecting the scanning lines; a common line driving circuit for inverting the voltage of the common electrode for a predetermined period of one horizontal scanning period or more with a predetermined potential as a reference; and the scanning line A data line driving circuit for supplying an image signal to the data line in a selected period, and the data line driving circuit has a plurality of output terminals with respect to one input terminal,
By connecting an output terminal selected from the plurality of output terminals to the input terminal,
A plurality of demultiplexer unit circuits for distributing image signals supplied as time-division signals to the plurality of data lines, and specifying the first of the plurality of data lines to be selected after the voltage of the common electrode is inverted The demultiplexer unit circuit selects only the specific data line in the first period and sequentially selects the remaining data lines excluding the specific data line in the second period. .

According to the present invention, the first data line selected after the common electrode voltage is inverted among the plurality of data lines is set as the specific data line, and only the specific data line is selected in the first period by the demultiplexer unit circuit. In addition, the remaining data lines excluding the specific data line are sequentially selected in the second period.
When the voltage of the common electrode is inverted, the potential of the specific data line fluctuates. However, since the specific data line is selected in the first period, the pixel electrode related to the specific data line can be written in dummy. Insufficiency can be prevented and uneven color can be reduced.

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 the intersections of the scanning lines and the data lines, and a plurality of pixel electrodes opposed to the pixel electrodes. An electro-optical device comprising: a common electrode; and a plurality of switching elements that bring the data line and the pixel electrode into a conductive state or a non-conductive state based on a voltage applied to the scanning line,
A scanning line driving circuit for supplying a voltage for sequentially selecting the scanning lines; a common line driving circuit for inverting the voltage of the common electrode for a predetermined period of one horizontal scanning period or more with a predetermined potential as a reference; and the scanning line A data line driving circuit for supplying an image signal to the data line in a selected period, and the data line driving circuit has a plurality of output terminals with respect to one input terminal,
By connecting an output terminal selected from the plurality of output terminals to the input terminal,
A plurality of demultiplexer unit circuits for distributing image signals supplied as time-division signals to the plurality of data lines, and specifying the first of the plurality of data lines to be selected after the voltage of the common electrode is inverted The demultiplexer unit circuit selects at least two data lines including the specific data line among the plurality of data lines in a first period, and then selects only the specific data line in a second period. And the remaining data lines excluding the specific data line are sequentially selected in a period having the same length as the second period.

According to the present invention, the first data line selected after the voltage of the common electrode is inverted among the plurality of data lines is set as the specific data line, and the demultiplexer unit circuit sets at least two data lines including the specific data line. The selection is performed in the first period, and then only the specific data line is selected in the second period, and the remaining data lines excluding the specific data line are sequentially selected in the period having the same length as the second period.
Therefore, when the voltage of the common electrode is inverted, the potential of the specific data line fluctuates. However, since writing can be performed dummyly to the pixel electrodes related to at least two data lines including the specific data line, insufficient writing is prevented. , Color unevenness can be reduced.

In the above electro-optical device, the common line driving circuit lowers the potential of the common electrode from the potential of the pixel electrode, and the scanning line driving circuit sequentially selects the scanning lines.
The data line is selected by a demultiplexer unit circuit of the data line drive circuit, and positive writing for supplying an image signal to the selected data line, and the potential of the common electrode is set to the pixel by the common line drive circuit. The data line is selected by the demultiplexer unit circuit of the data line driving circuit while sequentially selecting the scanning line by the scanning line driving circuit with the potential higher than the potential of the electrode, and an image is displayed on the selected data line. It is preferable to perform negative polarity writing for supplying a signal.

According to the present invention, since the positive polarity writing and the negative polarity writing are performed, the polarity of the voltage applied to the liquid crystal can be reversed, and the deterioration of the liquid crystal can be prevented.

In the above electro-optical device, the demultiplexer unit circuit may select the specific data line continuously until the second period without selecting the specific data line in the first period. preferable.

According to the present invention, after the specific data line is selected in the first period, it is continuously selected up to the second period without being in a non-selected state. Therefore, the demultiplexer unit circuit is turned on,
Since the number of turn-offs can be reduced, the burden on the demultiplexer unit circuit can be reduced and the power consumption can be reduced.

  An electronic apparatus according to an aspect of the invention includes the above-described electro-optical device.

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.
<First Embodiment>
FIG. 1 is a block diagram showing a configuration of an electro-optical device 1 according to the first embodiment of the present invention.
The electro-optical device 1 employs an H / common inversion driving method, and includes a liquid crystal panel AA and a backlight unit (not shown). The liquid crystal panel AA includes a display area A having a plurality of pixels 50, a scanning line driving circuit 20 provided around the display area A to drive the pixels 50, a data line driving circuit 30, and a common line driving circuit. 40.

The liquid crystal panel AA includes m (m is a natural number of 2 or more) scanning lines Y1 to Ym and common lines (capacitance lines) Z1 to Zm, which are alternately provided at predetermined intervals, and these scanning lines Y and common lines. N (n is a natural number of 2 or more) data lines X intersecting Z and provided at predetermined intervals
1 to Xn, and the pixel 50 is provided at an intersection of each scanning line Y and each data line X.

The pixel 50 includes a pixel transistor 51, a pixel electrode 55, a common electrode 56 facing the pixel electrode 55, and an accumulation in which one end is electrically connected to the pixel electrode 55 and the other end is electrically connected to the common line Z. The capacitor 53 is configured.

A scanning line Y is connected to the gate electrode of the pixel transistor 51, and the pixel transistor 51
The data line X is connected to the source electrode, and the drain electrode of the pixel transistor 51 is connected to the source electrode of
The pixel electrode 55 and the storage capacitor 53 are connected. In addition, the pixel electrode 55 and the common electrode 56
A liquid crystal as an electro-optical material is sandwiched between the two. Therefore, when the selection voltage is applied from the scanning line Y, the pixel transistor 51 brings the data line X, the pixel electrode 55, and the storage capacitor 53 into conduction.

The common electrode 56 includes conductive portions 41 provided at the four corners of the liquid crystal panel AA and the conductive portions 4.
The common line Z is connected to the common line Z through the common wiring 42 that connects the two.

The scanning line driving circuit 20 applies a selection voltage for turning on the pixel transistor 51 to the scanning line Y1.
-Sequentially supplied to Ym. For example, when a selection voltage is supplied to a certain scanning line Y, all the pixel transistors 51 connected to the scanning line Y are turned on, and all the pixels 50 related to the scanning line Y are selected.

The common line drive circuit 40 supplies a drive signal having a negative first potential or a positive second potential higher than the first potential to the common line Z. Specifically, the common line driving circuit 40 includes:
The polarity is inverted every one horizontal scanning period between the negative first potential and the positive second potential.

The data line driving circuit 30 includes a demultiplexer 31, and supplies an image signal to each data line X during a period in which the scanning line Y is selected, and the pixel of the pixel 50 through the pixel transistor 51 in a conductive state. Image data is sequentially written to the electrodes 55.
Here, when the potential of the common electrode 56 is the first potential, the data line driving circuit 30 supplies an image signal to the data line X with a positive potential higher than the first potential. When the potential is the second potential, the image signal is supplied to the data line X with a negative polarity potential lower than the second potential.

FIG. 2 is a block diagram of the demultiplexer 31.
The demultiplexer 31 includes a plurality of demultiplexer unit circuits M that can control six data lines X at a time. Here, although the leftmost one in FIG. 1 among these demultiplexer unit circuits M will be described, the other demultiplexer circuits have the same configuration.

The demultiplexer unit circuit M has six output terminals OT1 to OT1 for one input terminal IT.
The selected output terminal OT1 to OT6 is connected to the input terminal IT by selecting from these six output terminals OT1 to OT6. Output terminals OT1 to OT6 of the demultiplexer unit circuit M are connected to data lines X1 to X6, respectively.
As a result, the image signal supplied as a time division signal from the signal source is converted into the data lines X1 to X6.
Sort out.

Specifically, the demultiplexer unit circuit M includes first to sixth switching elements 61 to 66, respectively. One source electrodes of the first to sixth switching elements 61 to 66 are all connected to the input terminal IT, and the drain electrodes are output terminals OT1 to OT6, respectively.
It is connected to the. The gate electrodes of the first to sixth switching elements are the control terminals SEL.
1 to SEL6.

An image signal in which image data of each color of R (red), G (green), and B (blue) is multiplexed in a time division manner is supplied to the input terminal IT from a signal source (not shown).
Control signals for selecting one of the first to sixth switching elements 61 to 66 are supplied to the control terminals SEL1 to SEL6 of the first to sixth switching elements 61 to 66.

The above demultiplexer 31 operates as follows.
An image signal is supplied to the input terminal IT of the demultiplexer unit circuit M, and a control signal is supplied to the control terminals SEL1 to SEL6.
Then, according to the control signal, the first to sixth switching elements 61 to 66 are sequentially turned on. Thereby, the image signal is sequentially distributed to the output terminals OT1 to OT6.

The above electro-optical device 1 operates as follows.
In other words, all the pixels 50 associated with each scanning line Y are sequentially selected by supplying the selection voltage from the scanning line driving circuit 20 in a line sequential manner. In synchronization with the selection of the pixels 50, the data line X is selected by the demultiplexer 31, and an image signal is supplied from the data line driving circuit 30 to the selected data line X. Thus, an image signal is supplied from the data line X to the pixel electrode 55 to all the pixels 50 selected by the scanning line driving circuit 20 and the data line driving circuit 30, and the image data is written to the pixel electrode 55.

Here, in the electro-optical device 1, the common line driving circuit 40 inverts the potential of the common electrode 56 between the first potential and the second potential. When the potential of the common electrode 56 is the first potential, the data line driving circuit 30 supplies an image signal to the data line X at a potential higher than the first potential (
Hereinafter, when the potential of the common electrode 56 is the second potential, the data line driving circuit 30 supplies the image signal to the data line X at a potential lower than the second potential (hereinafter referred to as positive polarity writing). Hereinafter, this is referred to as negative polarity writing).

When image data is written to the pixel electrode 55 of the pixel 50, a driving voltage is applied to the liquid crystal due to a potential difference between the pixel electrode 55 and the common electrode 56. Therefore, by changing the voltage level of the image signal, the orientation and order of the liquid crystal are changed, and gradation display by light modulation of each pixel 50 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 orders of magnitude longer than the period during which image data is written.

FIG. 3 is a timing chart of the demultiplexer 31.
After the horizontal synchronization signal Hsync changes from L level to H level, the control terminal SEL1 changes to H level twice from time t1 to t4. At this time, the periods during which the signals are at the H level are T.
Therefore, the image signal is supplied from the output terminal OT1 to the data line X1 during the period 2T as the first period, and the image data is written to the pixel electrode 55 related to the data line X1.
Note that since the interval of the period during which the control terminal SEL1 is at the H level is short, the image signal is output almost continuously to the data line X1.

At time t5 to t6, the control terminal SEL2 becomes H level during the period T as the second period. Therefore, an image signal is supplied to the data line X2 from the output terminal OT2 during the period T, and image data is written to the pixel electrode 55 related to the data line X2.

At times t7 to t14, the control terminals SEL3 to SEL6 are similar to the times t5 to t6.
Sequentially become H level during the period T. Therefore, the image signals are supplied to the data lines X3 to X6 from the output terminals OT3 to OT6 during the period T, respectively, and the image data is sequentially written to the pixel electrodes 55 related to the data lines X3 to X6.

As described above, image data is written to the data line X1 during the period 2T, and image data is written to the remaining data lines X2 to X6 during the period T.

According to this embodiment, there are the following effects.
(1) The data line X1 is selected first after the voltage of the common electrode 56 is inverted among the six data lines X1 to X6, and the demultiplexer unit circuit M selects only the data line X1 in the period 2T. At the same time, the remaining data lines X2 to X6 excluding the data line X1 are sequentially selected in the period T.
When the common electrode 56 is inverted, the potential of the data line X1 changes, but the data line X1 is changed to the first.
Since the period 2T is selected, dummy writing can be performed on the pixel electrode 55 related to the data line X1, and thus insufficient writing can be prevented and color unevenness can be reduced.

(2) The polarity of the voltage applied to the liquid crystal can be reversed because the common line driving circuit 40 inverts the potential of the common line Z every horizontal scanning period and performs positive polarity writing and negative polarity writing. , Can prevent the deterioration of the liquid crystal.

Second Embodiment
In this embodiment, only the operation of the demultiplexer 31 is different from that of the first embodiment, and other configurations are the same as those of the first embodiment.
FIG. 4 is a timing chart of the demultiplexer 31 of the electro-optical device 1 according to the second embodiment of the invention.
After the horizontal synchronization signal Hsync changes from the L level to the H level, at the time ta1 to ta2, the control terminals SEL1 to SEL3 are set to the H level during the period TA1 as the first period. Therefore, the image signals are supplied to the data lines X1 to X3 from the output terminals OT1 to OT3 during the period TA1, and the image data is written to the pixel electrodes 55 related to the data lines X1 to X3.

From time ta3 to ta4, the control terminal SEL1 is at the H level during the period TA2 as the second period. Therefore, an image signal is supplied from the output terminal OT1 to the data line X1 during the period TA2, and image data is written to the pixel electrode 55 associated with the data line X1.

At times ta5 to ta8, as with times ta3 to ta4, control terminals SEL2, S
EL3 sequentially becomes H level during the period TA2. Therefore, image signals are supplied to the data lines X2 and X3 from the output terminals OT2 and OT3, respectively, during the period TA2, and image data is sequentially written to the pixel electrodes 55 associated with the data lines X2 and X3.

From time ta9 to ta10, similarly to time ta1 to ta2, image data is written to the pixel electrodes 55 associated with the data lines X4 to X6 during the period TA1.

At times ta11 to ta16 as well as at times ta3 to ta4, during the period TA2,
Image data is sequentially written to the pixel electrodes 55 related to the data lines X3 to X6.

As described above, image data is written into the data lines X1 to X6 during the period TA1 + TA2.

In the present embodiment, the control terminals SEL1 to SEL3 are set to the H level during the period TA1, but not limited to this, only the control terminals SEL1 and SEL2 may be set to the H level during the period TA1.

According to the present embodiment, in addition to the above-described effect (2), the following effect can be obtained.
(3) Among the six data lines X1 to X6, the data line X1 is selected first after the voltage of the common electrode 56 is inverted, and the demultiplexer unit circuit M includes the data lines X1 to X1 including the data line X1. X3 is selected in period TA1, and then only data line X1 is selected in period TA2.
The remaining data lines X2 and X3 excluding the data line X1 are selected in the period TA2.
Further, the data lines X4 to X6 including the data line X4 are selected in the period TA1, and then only the data line X4 is selected in the period TA2, and the remaining data lines X5 and X6 excluding the data line X4 are selected in the period TA2. .
Therefore, when the voltage of the common electrode 56 is inverted, the potential of the data line X1 changes.
Since dummy writing can be performed on the pixel electrodes 55 related to all the data lines X1 to X3 including the data line X1, insufficient writing can be prevented and color unevenness can be reduced.

<Third Embodiment>
In the present embodiment, only the operation of the demultiplexer 31 is different from the first embodiment.
FIG. 5 is a timing chart of the demultiplexer 31 of the electro-optical device 1 according to the third embodiment of the invention.
After the horizontal synchronization signal Hsync changes from the L level to the H level, at time tb1, the control terminals SEL1 to SEL3 become the H level. Therefore, image signals are supplied from the output terminals OT1 to OT3 to the data lines X1 to X3, and the pixel electrodes 55 related to the data lines X1 to X3.
The image data begins to be written to.

At time tb2, only the control terminal SEL1 becomes L level, and writing of the image data of the pixel electrode 55 related to the data line X1 is completed.

At time tb3, following the control terminal SEL1, the control terminal SEL2 also becomes L level, and writing of the image data of the pixel electrode 55 related to the data line X2 is completed.

At time tb4, following the control terminals SEL1 and SEL2, the control terminal SEL3 also becomes L level, and writing of the image data of the pixel electrode 55 related to the data line X3 is completed.

At time tb5, the control terminals SEL4 to SEL6 become H level. Therefore, image signals are supplied to the data lines X4 to X6 from the output terminals OT4 to OT6, and the data lines X4
Image data starts to be written to the pixel electrodes 55 related to .about.X6.

At time tb6, only the control terminal SEL4 becomes L level, and the writing of the image data of the pixel electrode 55 related to the data line X4 is completed.

At time tb7, following the control terminal SEL4, the control terminal SEL5 also becomes L level, and writing of the image data of the pixel electrode 55 related to the data line X5 is completed.

At time tb8, following the control terminals SEL4 and SEL5, the control terminal SEL6 also becomes L level, and writing of the image data of the pixel electrode 55 related to the data line X6 is completed.

As described above, image data is written into the data lines X1 and X4 during the period TB1 as the first period, and the data lines X2 and X5 have a period TB2 longer than the period TB1 as the second period. In the meantime, image data is written, and image data is written into the data lines X3 and X6 for a period TB3 longer than the period TB2 as the second period.

According to the present embodiment, in addition to the above-described effect (2), the following effect can be obtained.
(4) Among the six data lines X1 to X6, the data line X1 is selected first after the voltage of the common electrode 56 is inverted. The demultiplexer unit circuit M causes the data lines X1 to X1 including the data line X1 to be selected. X3 is selected in period TB1, and then data lines X2, X3
As a result, the data line X2 is selected in the period TB2, and the data line X3 is selected in the period TB3.
Selected with.
Further, the data lines X4 to X6 including the data line X4 are selected in the period TB1, and subsequently, the data lines X5 and X6 are selected. As a result, the data line X5 is selected in the period TB2,
Data line X6 was selected in period TB3.
Therefore, when the voltage of the common electrode 56 is inverted, the potential of the data line X1 changes.
Since dummy writing can be performed on the pixel electrodes 55 related to all the data lines X1 to X3 including the data line X1, insufficient writing can be prevented and color unevenness can be reduced.

<Modification>
It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
For example, in the first and second embodiments described above, after the data line X1 is first selected, the data line X1 is selected again at a predetermined interval. However, the present invention is not limited to this. That is, the data line X1
After selecting, the data line X1 may be selected continuously without being deselected.

If it does in this way, in addition to the effect of (1)-(3) mentioned above, there exist the following effects.
The data line X1 was selected continuously without being deselected. Therefore, since the number of times the demultiplexer unit circuit M is turned on and off can be reduced, the burden on the demultiplexer unit circuit M can be reduced and the power consumption can be reduced.

For example, in each of the above-described embodiments, 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. As an electrophoretic display panel, 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. 6 is a perspective view illustrating 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 includes a personal computer, an information portable terminal, a digital still camera, a liquid crystal television, a viewfinder type, a monitor direct view type video tape recorder, a car navigation system as well as those shown in FIG. 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. The electro-optical device described above can be applied as a display unit of these various electronic devices.

1 is a block diagram illustrating a configuration of an electro-optical device according to a first embodiment of the invention. FIG. FIG. 3 is a block diagram of a demultiplexer unit circuit constituting a data line driving circuit of the electro-optical device. 4 is a timing chart of the demultiplexer unit circuit. 6 is a timing chart of a demultiplexer unit circuit constituting a data line driving circuit of an electro-optical device according to a second embodiment of the invention. 12 is a timing chart of a demultiplexer unit circuit constituting a data line driving circuit of an electro-optical device according to a third embodiment of the invention. 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, 20 ... Scanning line drive circuit, 30 ... Data line drive circuit, 40 ... Common line drive circuit, 51 ... Pixel transistor (switching element), 55 ... Pixel electrode, 56 ... Common electrode, 3000 ... Mobile phone (Electronic equipment), M ... demultiplexer unit circuit, IT ... input terminal, OT1 to OT6 ... output terminal, X ... data line, X1 ... specific data line, Y ... scanning line, first period ... 2T, TA1, TB1 Second period T, TA2, TB2, TB3.

Claims (5)

A plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to the intersection of the scanning lines and the data lines, a plurality of common electrodes opposed to the pixel electrodes, and the scanning lines An electro-optical device comprising: a plurality of switching elements that bring the data line and the pixel electrode into a conductive state or a non-conductive state based on an applied voltage;
A scanning line driving circuit for supplying a voltage for sequentially selecting the scanning lines;
A common line driving circuit for inverting the voltage of the common electrode in a predetermined period of one horizontal scanning period or more with a predetermined potential as a reference;
A data line driving circuit for supplying an image signal to the data line in a period in which the scanning line is selected,
The data line driving circuit has a plurality of output terminals for one input terminal, and supplies the time-division signal by connecting an output terminal selected from the plurality of output terminals to the input terminal. A plurality of demultiplexer unit circuits that distribute the image signal to be divided into the plurality of data lines,
Among the plurality of data lines, a specific data line is selected first after the voltage of the common electrode is inverted,
The demultiplexer unit circuit selects only the specific data line in a first period, and sequentially selects the remaining data lines excluding the specific data line in a second period. A plurality of scanning lines, a plurality of data lines, a plurality of pixel electrodes provided corresponding to the intersection of the scanning lines and the data lines, a plurality of common electrodes opposed to the pixel electrodes, and the scanning lines An electro-optical device comprising: a plurality of switching elements that bring the data line and the pixel electrode into a conductive state or a non-conductive state based on an applied voltage;
A scanning line driving circuit for supplying a voltage for sequentially selecting the scanning lines;
A common line driving circuit for inverting the voltage of the common electrode in a predetermined period of one horizontal scanning period or more with a predetermined potential as a reference;
A data line driving circuit for supplying an image signal to the data line in a period in which the scanning line is selected,
The data line driving circuit has a plurality of output terminals for one input terminal, and supplies the time-division signal by connecting an output terminal selected from the plurality of output terminals to the input terminal. A plurality of demultiplexer unit circuits that distribute the image signal to be divided into the plurality of data lines,
Among the plurality of data lines, a specific data line is selected first after the voltage of the common electrode is inverted,
The demultiplexer unit circuit selects at least two data lines including the specific data line among the plurality of data lines in a first period, and then selects only the specific data line in the second period.
And the remaining data lines excluding the specific data line are sequentially selected in a period having the same length as the second period. The common line driving circuit makes the potential of the common electrode lower than the potential of the pixel electrode, and the scanning line driving circuit sequentially selects the scanning lines, while the demultiplexer unit circuit of the data line driving circuit Positive polarity writing that selects a data line and supplies an image signal to the selected data line;
The common line driving circuit makes the potential of the common electrode higher than the potential of the pixel electrode, and the scanning line driving circuit sequentially selects the scanning lines, while the demultiplexer unit circuit of the data line driving circuit The electro-optical device according to claim 1, wherein a data line is selected and negative polarity writing is performed to supply an image signal to the selected data line. 3. The demultiplexer unit circuit according to claim 2, wherein after the specific data line is selected in the first period, the demultiplexer unit circuit is continuously selected until the second period without being selected. The electro-optical device described.   An electronic apparatus comprising the electro-optical device according to claim 1.

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