JP2007164019A - Electro-optical device, driving method, driving circuit, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of vertical and horizontal crosstalk and to reduce power consumption. <P>SOLUTION: Scan lines are selected per row for every horizontal scanning period. The horizontal scanning period is divided into a first half period Ta and a latter half period Tb, and when a selection voltage having one of a positive polarity and a negative polarity is applied to a selected scan line in the latter half period Tb, a selection voltage having the other of a positive polarity and a negative polarity is applied to the next scan line in the latter half period Tb of the horizontal scanning period. If the selection voltage having the positive polarity is applied in the latter half period Tb, an ON voltage application period is temporally deflected backward in the half latter period of the horizontal scanning period and a voltage in the latter half period is inverted in the first half period Ta of the horizontal scanning period with respect to data signals Xj of odd columns, and an ON voltage application period is temporally deflected forward in the half latter period of the horizontal scanning period and a voltage in the latter half period Tb is inverted in the first half period Ta of the next horizontal scanning period with respect to data signals X(j+1) of even columns. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for displaying an image using an electro-optical material such as liquid crystal.

As a technique for displaying a plurality of gradations in an electro-optical device such as a liquid crystal device, a pulse width modulation method has been proposed. In this method, an on-voltage for displaying a pixel on and an off-voltage for displaying off a pixel are applied to each data line in a time distribution according to the gradation of the pixel (see, for example, Patent Document 1). . In electro-optical devices that employ this method,
Since the voltage of the data line is only a binary value of an on voltage and an off voltage, there is an advantage that the configuration for driving the electro-optical device can be simplified.
JP 2002-366120 A (see FIG. 10)

By the way, in this type of electro-optical device, each data line is capacitively coupled to another data line adjacent thereto. Therefore, when the voltage of one of the data lines is switched from one of the on-voltage and the off-voltage to the other, the voltage of the other data line adjacent to the data line also varies. When the voltage of each data line varies as described above, the target voltage effective value cannot be applied to each pixel, and as a result, display unevenness along the direction in which the data line extends (hereinafter, referred to as “data unevenness”). Then, this phenomenon is called “vertical crosstalk”.
In order to solve this problem, (1) measures to reduce the parasitic capacitance in the data line, (2)
A measure to increase the capacity of the pixel as compared with the capacity of the data line is considered. However, since there is a limit to the reduction of the data line capacity and the increase of the pixel capacity, measures (1) and (2
) Also makes it difficult to sufficiently suppress vertical crosstalk.

Further, in an electro-optical device having a scanning line that functions as an electrode of a pixel and a data line that intersects the scanning line while maintaining insulation, the capacity of the scanning line is increased in order to adopt the measure (2). It is necessary to make it. In this configuration, when the scanning line and the data line are capacitively coupled, the voltage of the scanning line fluctuates due to the fluctuation of the voltage applied to the data line. Due to the fluctuation, display unevenness (so-called lateral crosstalk) may occur in the direction in which the scanning line extends. Here, since the voltage fluctuation amount of the scanning line according to the voltage of the data line increases according to the capacity of the scanning line, when the measure (2) for increasing the capacity of the pixel (capacity of the scanning line) is adopted. This time, there may be a problem that lateral crosstalk becomes apparent.
The present invention has been made in view of such circumstances, and an object of the present invention is to reduce vertical crosstalk and horizontal crosstalk without being restricted by the capacity of data lines or pixels. An electro-optical device, a driving method, a driving circuit, and an electronic apparatus are provided.

In order to achieve the above object, there is provided a driving method of an electro-optical device for driving a plurality of pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines, wherein the plurality of scanning lines are One row is selected for each horizontal scanning period, and positive and negative selection voltages are alternately applied to the selected scanning line with respect to the reference voltage in the latter half of the horizontal scanning period. In the period, when one of the positive polarity and the negative polarity selection voltage is applied, a predetermined on-voltage is applied to a data line belonging to one of the odd or even columns among the plurality of data lines. Applying a selection voltage to a pixel in accordance with the gray level of the pixel to which the selection voltage is applied, and applying a predetermined off-voltage in a period in which the on-voltage is not applied in the latter half period, and the horizontal Run In the first half of the period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance, and the on voltage is applied to a data line belonging to the other of the odd or even columns among the plurality of data lines. In the latter half period, and applied in the period corresponding to the gray level of the pixel to which the selection voltage is applied, and the off voltage is applied in the period in which the on voltage is not applied in the latter half period. In addition, in the first half period of the horizontal scanning period next to the horizontal scanning period, a waveform in which the on voltage and the off voltage in the second half period are switched is applied, while the other of the positive polarity and the negative polarity is selected. When a voltage is applied, the ON voltage is applied to the data line belonging to one of the odd or even columns among the plurality of data lines, and the selection voltage is selected during the latter half period. The time period corresponding to the gradation of the pixel to be applied is applied by moving forward in time, the off voltage is applied in the second half period in which the on voltage is not applied, and the first half period of the horizontal scanning period In the second half period, a waveform in which the ON voltage and the OFF voltage are switched in advance is applied in advance, and the ON voltage is applied to the data line belonging to the other of the odd or even columns among the plurality of data lines.
In the latter half period, the selection voltage is applied backward in time for a period corresponding to the gradation of the pixel, and in the latter half period, the off voltage is applied in the period in which the on voltage is not applied, In the first half of the horizontal scanning period next to the horizontal scanning period, a waveform in which the on voltage and the off voltage in the second half period are switched is applied.
In this driving method, a selection voltage may be applied to the scanning line during the first half of the horizontal scanning period, or an on or off voltage may be applied over the entire selection voltage application period. According to the present invention, it is possible to eliminate display quality due to vertical crosstalk and horizontal crosstalk and to reduce power consumption.
The present invention is not limited to the driving method of the electro-optical device, and can be conceptualized as a driving circuit of the electro-optical device, an electro-optical device, and an electronic apparatus having the electro-optical device.

  Embodiments of the present invention will be described below with reference to the drawings.

<Overall configuration>
FIG. 1 is a block diagram illustrating a configuration of an electro-optical device according to an embodiment of the invention. As shown in the figure, the electro-optical device 10 includes an electro-optical panel 100, a control circuit 400, a gradation control pulse generation circuit 450, and a voltage generation circuit 500.
Among these, the electro-optical panel 100 includes 320 scanning lines 3 extending in the X direction (row direction).
12 and an element substrate on which 240 columns of data lines 212 extending in the Y direction (column direction) are bonded to each other, and liquid crystal is sealed in a gap between these substrates. It has been stopped.
The scanning line 312 is an electrode obtained by patterning a conductive material having optical transparency such as ITO (Indium Tin Oxide) into a strip shape. A pixel 116 is formed at each point where the scanning line 312 and the data line 212 intersect in plan view. Therefore, in this embodiment,
The pixels 116 are arranged in a matrix of 320 vertical rows × 240 horizontal columns, but the present invention is not limited to this arrangement.

Here, for convenience of description, the configuration of the pixel 116 will be described. FIG. 2 is a diagram illustrating a configuration of the pixel 116. In either case, a configuration of a total of 4 pixels of 2 × 2 corresponding to the intersection of the i-th row and the (i + 1) th row adjacent thereto and the j-th column and the (j + 1) th row adjacent thereto is shown. ing.
Note that i and (i + 1) are symbols for generally indicating the row of the scanning line in which the pixels 116 are arranged, and are integers of 1 to 320, where i is an odd number (1, 3, 5, ... 3
19) and (i + 1) is an even number (2, 4, 6,..., 320). Also, j, (j
+1) is a symbol for generally indicating a column of data lines in which the pixels 116 are arranged, and is an integer of 1 to 240, where j is an odd number (1, 3, 5,... 219). )age,(
j + 1) is an even number (2, 4, 6,..., 240).

In FIG. 2, each pixel 116 has a configuration in which a serial connection of a TFD (Thin Film Diode) element 220 and a liquid crystal capacitor 118 is electrically inserted at the intersection of the scanning line 312 and the data line 212. It has become.
Among these, the TFD element 220 has a conductor / insulator / conductor laminated structure, and has diode switching characteristics in which current-voltage characteristics are nonlinear in both positive and negative directions. The liquid crystal capacitor 118 has the pixel electrode 119 as one electrode and the scanning line 312 as the other electrode.
The liquid crystal is sandwiched between both electrodes. Here, the pixel electrode 119 is a substantially rectangular electrode formed on the surface of the element substrate, and the pixel electrodes 119 in one row of pixels in the same row are arranged so as to face the scanning lines 312 in the row. To do.

In this pixel 116, when any one of the selection voltages ± Vs described later is applied to the scanning line 312, regardless of the voltage of the data signal applied to the data line 212, the scanning line and the data line are crossed. The corresponding TFD element 220 is forcibly turned on (ON),
Through the turned-on TFD element 220, the liquid crystal capacitor 118 is charged with a voltage corresponding to the difference between the selected voltage and the voltage of the data signal. Thereafter, the non-selection voltage ± Vd is applied to the scanning line 312.
Is applied, the TFD element 220 is turned off (off), and the voltage holding state in the liquid crystal capacitor 118 is maintained.
In the liquid crystal capacitor 118, the alignment state of the liquid crystal changes in accordance with the held voltage, so that the amount of light passing through the polarizer (not shown) is determined by the effective voltage value held in the liquid crystal capacitor 118.
For this reason, the voltage held in the liquid crystal capacitor 118 is controlled for each pixel by the voltage of the data line when the selection voltage is applied (in this embodiment, the temporal distribution of the on voltage and the off voltage). A predetermined gradation is displayed.
In this embodiment, for convenience of explanation, when the voltage effective value is small, the light transmittance increases and white display is performed. On the other hand, as the voltage effective value increases, the amount of transmitted light decreases and finally black display is performed. It becomes normal white mode. Further, the unit period used as a reference for the effective voltage value here is, for example, a period of one frame (1F).

Here, in the period in which the selection voltage is applied to the scanning line, if the data signal is a constant analog voltage over the period according to the gradation value, it is necessary to prepare a large number of voltages according to the gradation value. This complicates the voltage generation circuit. Therefore, in the pixel configuration as shown in FIG. 2, the voltage of the data line is defined by the ratio of the application period of two different voltages, here, the voltage ± Vd (also used as a non-selection voltage). A method of controlling by pulse width modulation is common.

When gradation display is performed by pulse width modulation in this way, when focusing on the pulse application timing during the selection voltage application period, an on-voltage having a reverse polarity relationship to the selection voltage is
There can be roughly classified into a trailing edge method that moves backward in time (also referred to as a right alignment method) and a leading edge method that moves forward in time (also referred to as a left alignment method). In other words, the trailing edge method is a method in which the on-voltage application period is extended forward in time by a period corresponding to the gradation value with reference to the end of application of the selection voltage (in other words, the off-voltage method). The application period is extended backward in time by a period corresponding to the gradation value with reference to the start of application of the selection voltage). Conversely, the leading edge method selects the application period of the on-voltage. The time period is extended backwards by a period corresponding to the gradation value with reference to the start of voltage application (in other words, the application period of the off-voltage is determined with reference to the end of application of the selected voltage. It is extended forward in time by a period according to the value).
There are two types of selection voltage, positive voltage + Vs and negative voltage -Vs.
The on-state voltage is negative voltage −Vd during the application period of positive voltage + Vs, and is positive voltage + Vd during the application period of negative voltage −Vs. Further, there is an off voltage as a concept opposite to the on voltage. This off-voltage is the same positive voltage + Vd during the application period of the positive voltage + Vs, and the same negative voltage -Vd during the application period of the negative voltage -Vs.

Returning to FIG. 1, the control circuit 400 generates various control signals according to the control signal Cont supplied from a host circuit (not shown) and supplies the control signals to the electro-optical panel 100. The gradation control pulse generation circuit 450 individually generates a trailing edge scheme gradation control pulse Gcp-a and a leading edge scheme gradation control pulse Gcp-b in accordance with the control signal Cont. It supplies to the optical panel 100. Note that signals generated by the control circuit 400 and gradation control pulses Gcp-a and Gcp-b will be described later.
The voltage generation circuit 500 generates voltages ± Vs and ± Vd and supplies them to the electro-optical panel 100. In the present embodiment, the voltage ± Vs is used as the selection voltage of the scanning signal as described above, and the voltage ± Vd is shared by the non-selection voltage of the scanning signal and the voltage of the data signal. For this reason,
Both the voltage ± Vs and the voltage ± Vd are supplied to the scanning line driving circuit 350, and only the voltage ± Vd is supplied to the data line driving circuit 250. Note that separate voltage values may be used without using both the non-selection voltage of the scanning signal and the data signal.
On the other hand, in the electro-optical panel 100, a scanning line driving circuit 350 and a data line driving circuit 250 are mounted on an element substrate.

<Scanning line drive circuit>
Next, the scanning line driving circuit 350 will be described. The scanning line driving circuit 350 sequentially selects each scanning line 312 for each horizontal scanning period (1H), and selects the selected scanning line 312 in the second half period Tb of the horizontal scanning period (1H) in this embodiment. One of the voltages ± Vs is applied, while one of the non-selection voltages ± Vd is applied to the other scanning lines 312. For this reason, in this embodiment, even if the scanning line 312 is selected in the horizontal scanning period (1H), not the selection voltage but the non-selection voltage is applied in the first half period Ta.

Here, the scanning line driving circuit 350 performs scanning lines 312 in the 1, 2, 3,.
.., Y320, respectively. In particular, when general description is made without specifying a row, the above-described symbol i is used to express Yi, Y (i + 1 ).
In the present embodiment, the scanning line 312 is formed on the counter substrate, but electrical connection between the element substrate and the counter substrate is made for each scanning line by a conductive material (not shown). For this reason, the scanning line driving circuit 350 mounted on the element substrate is configured to supply a scanning signal to the scanning line 312 formed on the counter substrate through the conductive material.

As shown in FIG. 3, the scanning line driving circuit 350 uses the start pulse DY supplied at the beginning of the frame period (1F) as the clock signal CLY whose one period is the horizontal scanning period (1H).
The scanning lines 312 are sequentially selected every horizontal scanning period by the shift signal (not shown).
Then, the scanning line driving circuit 350 applies a voltage to each scanning line 312 as follows according to the selection. That is, if the polarity instruction signal FR-a is H level with respect to the scanning line 312 selected in a certain horizontal scanning period (1H), the scanning line driving circuit 350 is the latter half period Tb (0.5H) of the horizontal scanning period. ), The positive selection voltage + Vs is applied, and the non-selection voltage + Vd is applied after the lapse of the period. On the other hand, if the polarity instruction signal FR-a is at the L level, the second half period Tb of the selected horizontal scanning period is applied. Then, the negative selection voltage -Vs is applied, and after the period, the non-selection voltage -Vd is selected.

The polarity instruction signal FR-a is a signal that designates the positive polarity of the selection voltage if it is at the H level, and that designates the negative polarity if it is the L level. As shown in FIG. (1
In F), the polarity is inverted every horizontal scanning period (1H), and even if attention is paid to the same horizontal scanning period in adjacent frame periods, the polarity is inverted. Here, the reason why the polarity of the selection voltage is inverted is to prevent deterioration due to application of a direct current component to the liquid crystal.
In addition, with respect to the polarity, the high-order side has a positive polarity and the low-order side has a negative polarity with reference to a potential Vc (voltage zero) that is an intermediate value between the selection voltages + Vs and -Vs.

Therefore, the waveforms of the scanning signals Y1, Y2, Y3,..., Y320 are as shown in FIG.
More specifically, the scanning signal Yi supplied to the i-th scanning line 312 has a certain frame period (1F).
In the i-th horizontal scanning period, if the polarity instruction signal FR-a is at the H level, the selection voltage + Vs becomes the selection voltage + Vs in the latter half period Tb, and then the non-selection voltage + Vd having the same polarity as the selection voltage + Vs. Become. On the other hand, the scanning signal Y (i + 1) supplied to the scanning line 312 in the next (i + 1) th row is first scanned in the second half period Tb of the (i + 1) th horizontal scanning period.
The selection voltage −Vs has a polarity opposite to the selection voltage i, and then becomes a non-selection voltage −Vd having the same polarity as the selection voltage −Vs.
That is, the second half period Tb of each horizontal scanning period for each of the scanning lines 312 adjacent to each other.
A selection voltage (voltage + Vs or voltage -Vs) having a reverse polarity is alternately applied at, and after each horizontal scanning period, a non-selection voltage (with the same polarity as the selection voltage applied in the horizontal scanning period)
The cycle that voltage + Vd or voltage −Vd) is applied is repeated.
On the other hand, in the frame periods adjacent to each other on the time axis, the polarity of the selection voltage of the same scanning signal is reversed. For example, when the scanning signal Yi becomes a positive selection voltage + Vs in a certain frame, it becomes a negative selection voltage -Vs after one frame period.

The polarity instruction signal FR-b is not used in the scanning line driving circuit 350, but as shown in FIG. 3, the phase is delayed by 90 degrees (0.5H) with respect to the polarity instruction signal FR-a. In a relationship.

<Data line drive circuit>
Next, the data line driving circuit 250 will be described. In the horizontal scanning period in which the scanning line 312 of a certain row is selected by the scanning line driving circuit 350, the data line driving circuit 250 responds to the gradation value of the pixels 116 for one row positioned on the scanning line. A data signal having a different pulse width is supplied via the data line 212.
Here, the data signals supplied to the data lines 212 in the first, second, third,..., 240th columns are denoted as X1, X2, X3,. Further, when a data signal is expressed without specifying a column, it is expressed as Xj, X (j + 1) using the above-described symbols j, (j + 1).

FIG. 4 is a block diagram showing a configuration of the data line driving circuit 250. In this figure, the memory 252 has a storage area corresponding to a matrix arrangement of 320 rows × 240 columns, and each storage area has gradation data Ds for designating the gradation (brightness) of the corresponding pixel 116. Is stored, and at the start of a horizontal scanning period in which a certain scanning line 312 is selected, gradation data for one row of pixels located on the scanning line is read by a latch pulse LP.
Here, the gradation data is 3 bits in this embodiment, and the gradation value of the pixel is defined in 8 levels from G0 in the darkest state to G7 in the brightest state. As described above, in the present embodiment, since the normally white mode becomes brighter as the voltage effective value of the liquid crystal capacitor 118 becomes smaller, the voltage effective value of the liquid crystal capacitor 118 becomes the smallest in the case of the gradation value G7. As the gradation value decreases, the effective voltage value gradually increases, and control is performed so that the effective voltage value becomes maximum when the gradation value is G0. When the display contents are changed, the gradation data Ds for specifying the changed gradation value is supplied together with the write address from the upper circuit, and the gradation data Ds stored in the corresponding area is rewritten. It has a configuration.

In the present embodiment, the delay circuit 254 is provided corresponding to only even columns, and delays the gradation data read from the memory 252 by a half period (0.5H) of the horizontal scanning period.
Of the gradation data for one row of pixels read from the memory 252, the odd-numbered gradation data may be expressed as Da and the gradation data delayed by 0.5H may be expressed as Db.

Here, the gradation control pulse Gcp-a is used when a trailing edge type data signal is generated. As shown in FIG. 5 or FIG. 6, the first half period Ta and the second half period of one horizontal scanning period. In each of Tb, except for the lowest gradation value G0 and the highest gradation value G7, gradation values G1,
The data are output in an array corresponding to the order of G2,..., G6. For this reason, the gradation control pulse Gcp
The arrangement of -a defines the on-voltage application start timing corresponding to each of the gradation values G1, G2,..., G6 when defining the trailing edge type data signal, particularly in the latter half period Tb. become.
The gradation control pulse Gcp-b is used when generating a leading edge data signal. As shown in FIG. 5 or FIG. 6, the first half period Ta and the second half period Tb of one horizontal scanning period. , Except for the highest gradation value G7 and the lowest gradation value G0, the gradation values G6, G
Output in an array corresponding to the order of 5,..., G1. Therefore, the gradation control pulse Gcp-b
In the latter half period Tb in which the selection voltage is applied, the ON voltage application end timing corresponding to each of the gradation values G6, G5,. It will be.
Note that the arrangement of the gradation code pulses Gcp-a and Gcp-b in the figure is actually set in consideration of the voltage effective value-transmittance characteristic (VT characteristic) of the liquid crystal capacitor 118 and the like. For the gradation value G0, an on-voltage is applied over the entire second half period Tb during which the selection voltage is applied, and for the gradation value G7, an off-voltage is applied over the entire second half period Tb. In the present embodiment, there is no gradation control pulse corresponding to the gradation values G0 and G7.

On the other hand, the signal dRL is a signal that specifies whether to use the gradation control pulses Gcp-a or Gcp-b in the odd-numbered columns. In the present embodiment, the signal dRL is substantially the same as the polarity instruction signal FR-a as shown in FIG.
The signal RL is a signal having a relationship in which the phase of the signal dRL shown in FIG. 5 is advanced by 90 degrees (delayed by 270 degrees) (see FIG. 6), and the gradation control pulses Gcp-a and Gcp-b in the even columns. It is a signal which designates which one of these is used.

In the data line driving circuit 250, a double throw switch 256 corresponding to the odd number column is used.
And a double-throw switch 258 is also provided corresponding to the even-numbered columns. The odd-throw double throw switch 256 selects the gradation control pulse Gcp-a if the signal dRL is at the H level,
If the signal dRL is at the L level, the gradation control pulse Gcp-b is selected, while the even-throw double throw switch 258 selects the gradation control pulse Gcp-a if the signal RL is at the H level. Signal R
If L is at L level, the gradation control pulse Gcp-b is selected, and the selected one is output as the gradation control pulse Gcp in the corresponding column.

Therefore, the gradation control pulse Gcp selected by the odd-numbered switch 256 is equal to FIG.
As shown in FIG. 4, a certain scanning line 312 is selected in the horizontal scanning period (1H), and the positive polarity selection voltage + Vs is applied in the latter half period Tb (because the polarity instruction signal FR-a is at the H level). In this case, the gradation control pulse Gcp-a of the trailing edge system is applied over the first half period Ta and the second half period Tb of the horizontal scanning period (1H), while the negative selection voltage −
In the horizontal scanning period in which Vs is applied, the leading edge type gradation control pulse Gcp-b is formed over the first half period Ta and the second half period Tb.
In addition, as shown in FIG. 6, the grayscale control pulse Gcp selected by the even-numbered column switch 258 has a certain scanning line 312 selected in the horizontal scanning period, and the positive selection voltage + Vs in the latter half period Tb. When applied, the gray level control pulse Gcp-b of the leading edge method is applied from the latter half period Tb of the horizontal scanning period to the first half period Ta of the next horizontal scanning period, while the negative selection voltage − When Vs is applied, the trailing edge type gradation control pulse Gcp-a extends from the second half period Tb of the horizontal scanning period to the first half period Ta of the next horizontal scanning period.
Will be selected.

Here, the gradation control pulse Gcp selected by the odd-numbered column switch 256 is the signal dR.
Since it is supplied together with L to the decoder 260 described below, the decoder knows whether the gradation control pulse Gcp selected by the switch 256 is for the trailing edge method or the leading edge method. it can. The same applies to the decoders 260 of even columns.

The decoder 260 is provided corresponding to each column, and the decoder corresponding to a certain column generates a data signal corresponding to the column from gradation data corresponding to the column.
Among these, the decoder 260 in the odd-numbered column is the gradation data Da read from the memory 252.
The decoder 260 of the even number column generates various control signals from the grayscale data Db delayed by half the horizontal scanning period (0.5H) with respect to the odd number column. Is used to generate a data signal.

The control signal used in the odd-numbered column decoder 260 will be described. The latch pulse LP is a signal that defines the start of the horizontal scanning period (1H), as shown in FIG.
The reset signal Res is a signal that defines the start time of the first half period Ta and the second half period Tb of one horizontal scanning period as shown in FIG. As described above, the polarity instruction signal FR-a is a signal that specifies the polarity of the selection signal in the latter half period in the horizontal scanning period in which a certain scanning line 312 is selected (FIGS. 3 and 5). reference). As shown in FIG. 5, the signal MX-a is a signal obtained by advancing the phase of the polarity instruction signal FR-a by 90 degrees (delayed by 270 degrees).

Using such a control signal, the decoder 260 in the odd-numbered j columns can be used for one horizontal scanning period (1H).
At the start of the j-th gradation data Da read from the memory 252, the lowest gradation value G
When a gradation value other than 0 and the maximum gradation value G7 is designated, the voltage of the data signal Xj is defined as follows.
That is, when the latch pulse LP is output for the data signal Xj at the start of the first half period Ta of the horizontal scanning period, the odd-numbered column decoder 260 firstly has a negative voltage −Vd.
Second, at the timing when the grayscale control pulse Gcp corresponding to the grayscale value specified by the grayscale data Da is output, the positive polarity voltage + Vd is set. 3,
When the second half period Tb of the horizontal scanning period is reached, among the gradation control pulses Gcp, when the one corresponding to the gradation value specified by the gradation data Da is output again, the negative voltage −Vd Reset to.

Note that the gradation code pulse Gcp is reversed for the trailing edge method and the leading edge method, and the order of pulses corresponding to the gradation value is reversed, but the gradation control pulse of any method is supplied. As for the odd number column, it can be identified by the signal dRL as described above. For this reason, the count result is reset or set in the decoder 260 by the reset signal Res, and the gradation control pulse is counted up or down according to the logic level of the signal dRL. The timing corresponding to the gradation value can be discriminated when it matches the gradation value designated by.
For example, if the signal dRL is at the H level, the trailing edge type gradation control pulse Gcp-a is supplied. Therefore, when the signal Res is output, the count result is reset to “0” and If the tone control pulse is up-counted, the timing corresponding to the gradation value specified by the gradation data Da is the timing corresponding to the gradation value. If the signal dRL is at the L level, Since the leading edge type gradation control pulse Gcp-b is supplied, the count result is set to “7” when the signal Res is output, and if the gradation control pulse is down-counted, the count is increased. The timing corresponding to the gradation value is when the result matches the gradation value specified by the gradation data Da.

On the other hand, the decoder 260 for the odd-numbered j columns, if the grayscale data Da for the jth column read from the memory 252 specifies the lowest grayscale value G0 at the start of the horizontal scanning period (the first half period Ta). The signal Xj is a voltage corresponding to the logic level of the signal MX-a. That is, the decoder 260 in the odd-numbered j column sets the data signal Xj to the voltage + Vd over the period when the signal MX-a is at the H level and the data signal Xj to the voltage −Vd over the period when the signal MX-a is at the L level.
And
Further, the decoder 260 for the odd-numbered j columns, when the grayscale data Da read from the memory 252 specifies the highest grayscale value G7 at the start of the horizontal scanning period (the first half period Ta), The signal Xj is a voltage corresponding to the logic level obtained by inverting the signal MX-a. That is, the decoder 260 in the odd-numbered j column sets the data signal Xj to the voltage −Vd over the period when the signal MX-a is at the H level and sets the data signal Xj to the voltage + Vd over the period when the signal MX-a is at the L level.

Next, the control signal used in the decoder 260 in the even-numbered column will be described. The latch pulse dLP is delayed by half the horizontal scanning period (0.5H) by the delay circuit 262 shown in FIG. (See FIGS. 5 and 6). The reset signal Res is common to the odd-numbered decoders 260. The polarity instruction signal FR-b is shown in FIGS.
As shown in the figure, the polarity indicating signal FR-a is a signal that is in a relationship that is delayed by 90 degrees,
As shown in FIG. 6, the signal MX-b advances the phase of the polarity instruction signal FR-b by 90 degrees (27).
It is a signal that has a relationship of being delayed by 0 degrees.
Using such a control signal, the even-numbered (j + 1) -column decoder 260 has the j-column gradation data Da read from the delay circuit 254 at the start of the second half period Tb of one horizontal scanning period.
Designates a gradation value other than the lowest gradation value G0 and the highest gradation value G7, the voltage of the data signal X (j + 1) is defined as follows.
That is, when the latch pulse dLP is output for the data signal X (j + 1) at the start of the second half period Tb of the horizontal scanning period, the even (j + 1) column decoder 260 firstly has a negative polarity voltage. -Vd, and secondly, at the timing when the grayscale control pulse Gcp corresponding to the grayscale value specified by the grayscale data Db is output, the positive voltage + Vd is set. Third, when the first half period Ta of the next horizontal scanning period is reached, when the grayscale control pulse Gcp corresponding to the grayscale value specified by the grayscale data Db is output again, the negative polarity Reset to -Vd.
Note that the gradation code pulse Gcp supplied to the decoder 260 in the even (j + 1) -th column has the order of pulses corresponding to the gradation values reversed for the trailing edge method and the leading edge method. Which gradation control pulse is supplied can be identified by the signal RL in the even-numbered column as described above, and therefore corresponds to the gradation value in the same manner as the decoder 260 in the odd-numbered j-th column. Timing can be detected.

On the other hand, the decoder 260 of the even (j + 1) column has the lowest gradation value G0 of the gradation data Db of the (j + 1) column delayed by the delay circuit 254 at the start of the second half period Tb of the horizontal scanning period (1H). When specifying, the data signal X (j + 1) is a voltage corresponding to the logic level obtained by inverting the signal MX-b. That is, the even-numbered (j + 1) column decoder 260 sets the data signal Xj to the voltage −Vd over the period in which the signal MX-b is at the H level and sets the data signal Xj to the voltage + Vd over the period in which the signal MX-b is at the L level. To do.
The even (j + 1) column decoder 260 has the (j + 1) column gradation data Da delayed by the delay circuit 254 at the start of the second half period Tb of the horizontal scanning period (1H). When specifying, the data signal X (j + 1) is a voltage corresponding to the logic level of the signal MX-b. That is, the even-numbered (j + 1) column decoder 260 sets the data signal Xj to the voltage + Vd over the period in which the signal MX-b is at the H level and sets the data signal Xj to the voltage −Vd over the period in which the signal MX-b is at the L level. To do.

Here, an example of the voltage waveform of the odd-numbered j-column data signal Xj with respect to the gradation value specified by the gradation data Da is shown in FIG. 5, and the even (j + 1) -th column with respect to the gradation value specified by the gradation data Db. An example of the voltage waveform of the data signal X (j + 1) is shown in FIG. 6 for each representative gradation value.
That is, as shown in FIG. 5, in the voltage waveform of the data signal Xj in the odd-numbered j column, if the positive selection voltage + Vs is applied in the latter half period Tb of the horizontal scanning period, the selection voltage + Vs Indicates the end of the latter half period Tb of the horizontal scanning period as the application period of the negative polarity on-voltage -Vd having the opposite polarity increases as the gradation value increases, that is, as the gradation becomes darker in the normally black mode. It extends forward in time with respect to the reference (rear edge method).
In addition, in the voltage waveform of the data signal Xj in the odd-numbered j columns, if the negative selection voltage −Vs is applied in the second half period Tb of the horizontal scanning period, the positive polarity having the opposite polarity to the selection voltage −Vs. As the gradation value increases, the application period of the positive ON voltage + Vd extends backward in time with respect to the start of the second half period Tb of the horizontal scanning period (leading edge method).
Note that the odd-numbered j columns of data signals Xj are applied in the first half period Ta of the same horizontal scanning period at a ratio opposite to the ratio of the periods of the voltages + Vd and -Vd defined in the second half period Tb of the horizontal scanning period. The period of the voltage + Vd, −Vd is defined.

On the other hand, as shown in FIG. 6, in the voltage waveform of the data signal X (j + 1) in the even (j + 1) j columns, the positive selection voltage + Vs is applied in the second half period Tb of the horizontal scanning period. If so, the application period of the on-voltage -Vd extends backward in time with respect to the start time of the second half period Tb of the horizontal scanning period as the gradation value increases (leading edge method).
Further, in the voltage waveform of the data signal X (j + 1) in the even (j + 1) column, if the negative selection voltage −Vs is applied in the second half period Tb of the horizontal scanning period, the ON voltage + Vd is applied. As the gradation value increases, the period extends forward in time with respect to the end of the second half period Tb of the horizontal scanning period (rear edge method).
Note that the data signal X (j + 1) in the even (j + 1) column is the next horizontal scan at a ratio opposite to the ratio of the periods of the voltages + Vd and −Vd defined in the latter half period Tb of the horizontal scan period. Periods of voltages + Vd and −Vd applied in the first half period Ta of the period are defined.
5 and FIG. 6, the waveform of the data signal corresponding to the gradation values G1, G2, and G6 is omitted. Note that a hatched period in the data signal indicates an ON voltage application period.

In the present embodiment, the odd number j columns of data signals Xj shown in FIG. 5 and the even number (
The data signal X (j + 1) in the j + 1) column has a relationship shifted by a half period (0.5H) of the horizontal scanning period when the same gradation value is designated.
Therefore, when the odd number j column is considered as normal, the even number (j + 1) column is shifted by 0.5H.
Further, when the i-th scanning line is selected and the positive selection voltage + Vs is applied in the latter half period Tb of the horizontal scanning period, the odd-numbered j columns of the data signals Xj become the trailing edge system, and are even (j
The data signal X (j + 1) in the +1) column is of the leading edge type, and when the next (i + 1) -th scanning line is selected, the selection voltage applied in the latter half period Tb is a negative selection. In addition to the voltage −Vs, the odd-numbered j columns of data signals Xj have a leading edge format, and the even (j + 1) columns of data signals X (j + 1) have a trailing edge format.
Therefore, the writing to the pixel has a relationship as shown in FIG.

On the other hand, when the i-th scanning line is selected, the selection voltage applied in the second half period Tb is the negative selection voltage −Vs, and the odd-numbered j-column data signal Xj is the leading edge method. Even (j + 1) columns of data signals X (j + 1) are of the trailing edge system. When the next (i + 1) -th scanning line is selected, the selection voltage applied in the latter half period Tb is the positive selection voltage + Vs, and the odd-numbered j-column data signal Xj is a trailing edge method. The data signal X (j + 1) in the even (j + 1) column is the leading edge system.
Since the selection voltage applied to the i-th scanning line is inverted every frame, if writing to the pixel as shown in FIG. 9A is performed in n frames, the following (n + 1) ) In the frame, the relationship is as shown in FIG.

<Resolving vertical crosstalk>
By the way, since the 320 data lines 212 are arranged close to each other, each data line 2
12 is capacitively coupled to another data line 212 adjacent thereto. Therefore, when the voltage of each data line 212 is switched from one of the ON voltage and the OFF voltage to the other, the voltage of the other data line 212 adjacent to this data line 212 also varies.
Here, the conventional configuration in which the even number (j + 1) column data signal X (j + 1) is not shifted by 0.5 H with respect to the odd number j column data signal Xj, and all the data signals are unified by the trailing edge method. (Hereinafter referred to as “contrast configuration”) has a problem in that vertical crosstalk occurs due to voltage fluctuation of the data line 212. This problem will be described in detail as follows.

FIG. 14 shows an odd number j column data signal Xj and an even number (j
It is a figure which shows the waveform with the data signal X (j + 1) of a +1) column by the relationship with the scanning signals Yi and Y (i + 1).
Here, in the comparison configuration, when the pixels in the j and (j + 1) columns are continuously set to the lowest gradation value G0, if ideal, for example, in the horizontal scanning period in which the i-th scanning line 312 is selected. When the scanning signal Yi becomes the selection voltage + Vs in the second half period Tb, the data signals Xj and X (j + 1
) Becomes the voltage −Vd over the latter half period Tb, and becomes the voltage + Vd in the first half period Ta.
In the second half period Tb of the horizontal scanning period when the next (i + 1) -th scanning line 312 is selected, the scanning signal Y (i + 1) becomes the selection voltage −Vs, so that the data signals Xj and X (j + 1) ) Becomes the voltage + Vd over the latter half period Tb, and becomes the voltage −Vd in the first half period Ta.
In this case, the data signals Xj and X (j + 1) of the columns adjacent to each other are switched from one of the voltages + Vd and −Vd to the other at the same timing.
Rises to a voltage higher by ΔV than the original voltage + Vd as the voltage rises in the data signal X (j + 1) at the timing of switching from the voltage −Vd to the voltage + Vd. On the contrary, the data signal Xj falls to a voltage lower by ΔV than the original voltage −Vd as the voltage drops in the data signal X (j + 1) at the timing when the voltage + Vd switches to the voltage −Vd.
Similarly, since the data signal X (j + 1) is also affected by the voltage fluctuation of the data signal Xj, it rises to a voltage higher by ΔV than the voltage + Vd at the timing when the voltage −Vd switches to the voltage + Vd. At the timing of switching from the voltage + Vd to the voltage −Vd, the voltage −
The voltage drops to a voltage lower by ΔV than Vd. For this reason, the voltage amplitude of the data signals Xj and X (j + 1) is 2 (Vd + ΔV) which is 2ΔV larger than the ideal amplitude of 2Vd.

On the other hand, in the comparison configuration, when pixels in the j column are continuously set to the lowest gradation value G0 and pixels in the (j + 1) column are continuously set to the highest gradation value G7, the ideal case is shown in FIG. As
The data signal X (j + 1) has an inverted waveform of the data signal Xj having the gradation value G0. For this reason, at the timing when the data signal Xj switches from one of the voltages + Vd and -Vd to the other, the data signal X (
j + 1) is switched from one of the voltages + Vd and -Vd to the other.
Where the voltage + Vd is to be decreased by ΔV, the voltage −Vd is to be increased by ΔV. For this reason, the voltage amplitude of the data signals Xj and X (j + 1) is 2Vd which is an ideal amplitude.
2 (Vd−ΔV), which is smaller by 2ΔV.

As described above, the effective voltage value of the data line 212 in the j-th column is obtained when the adjacent (j + 1) -column pixels are continuously set to the gradation value G0 and when the gradation value G7 is continuously set. It will be very different.
Here, the voltage of the data line 212 in the j-th column is divided by the liquid crystal capacitor 118 and the capacitor of the TFD element 220 and then applied to the liquid crystal capacitor 118, but the voltage effective held in the liquid crystal capacitor 118 is effective. The value is ideally determined only by the selection voltage and the data voltage in the latter half period Tb in which the scanning line becomes the selection voltage, that is, the period in which the TFD element 220 is turned on, and in the period in which the non-selection voltage is other than that, Since the element 220 is turned off, it should not be affected by the data line voltage.
However, in the actual TFD element 220, the off resistance ideally does not become infinite in the off state to which the non-selection voltage is applied. Therefore, the liquid crystal capacitor 118 generates not a little off-leakage.
For this reason, for example, the gradation of the pixel in the i-th row and j-th column is not only determined by the selection voltage in the second half period Tb of the horizontal scanning period in which the scanning line in the i-th row is selected and the voltage of the data signal Xj, but also i This is influenced by the voltage of the data signal Xj during the period when the scanning line in the row is at the non-selection voltage.

Therefore, when the voltage effective value of the data signal Xj in the case where the pixels in the j column are continued at the lowest gradation value G0, the pixels in the adjacent (j + 1) column are continued at the same lowest gradation value G0. This is different from the case of continuous with different highest gradation values G7, which means that the brightness actually displayed in the pixels of the j columns that should be the lowest gradation value G0 is adjacent (j
+1) The gradation values of the pixels in the column are the same and the case where they are different from each other.
From another viewpoint, when two pixels in different columns are displayed with the same gradation, when the gradation of adjacent pixels in the two pixels is different in the two pixels, the same level is obtained in the two pixels. It means that the key cannot be maintained.
Such a change in the effective voltage value in the data line 212 occurs in units of the data line 212, so that the change in the gradation value is visually recognized along the vertical direction. This is the vertical crosstalk referred to in this case.
In this comparison configuration, all data signals are unified by the trailing edge method, but the same applies even when all data signals are unified by the leading edge method.

On the other hand, in the present embodiment, as shown in FIG. 7, when the pixels in the j column are continuously set to the lowest gradation value G0, the pixels in the (j + 1) column are also continuously set to the lowest gradation value. When G0 is set, the data signal Xj has a waveform obtained by delaying the phase of the data signal X (j + 1) by 90 degrees. For this reason, the data signal Xj is affected by the voltage rise in the data signal X (j + 1) after switching to the negative polarity side, while the data signal X (j + 1) is switched after switching to the positive polarity side. It will be affected by the voltage drop at.
On the other hand, when the pixels of the j column are continuously set to the lowest gradation value G0 and the pixels of the (j + 1) column are continuously set to the highest gradation value G7, the data signal Xj is conversely the data signal X (j The waveform is obtained by advancing the phase of +1) by 90 degrees. For this reason, the data signal Xj is affected by the voltage drop in the data signal X (j + 1) after being switched to the negative polarity side, while being switched to the positive polarity side,
The data signal X (j + 1) is affected by the voltage increase.
Further, when the pixels in the j column are continuously set to the lowest gradation value G0 and the pixels in the (j + 1) column are continuously set to the gradation values G0 and G7, the data signal Xj is the data signal X (j + Set the phase of 1) to 9
Since the relationship is shifted by 0 degrees (advanced or delayed), the adjacent data lines are not switched at the same time in the same direction.
Therefore, in this embodiment, the effective voltage value of the data signal Xj when the pixels in the j column are continuously set to the lowest gradation value G0 is the same as the lowest gradation value G of the pixels in the adjacent (j + 1) columns.
When it is continued at 0 and when it is continued at a different maximum gradation value G7, it can be made substantially the same, thereby making it possible to suppress the occurrence of the above-described vertical crosstalk.

<Resolving horizontal crosstalk>
Further, since each scanning line 312 faces the 320 data lines 212 through the liquid crystal, the scanning lines 312 are capacitively coupled to the data lines 212 in each column. Therefore, when the voltage of each data line 212 is switched from one of the on-voltage and the off-voltage to the other, the voltage of the scanning line 312 also varies.
For this reason, in the comparison configuration, apart from the above-described vertical crosstalk, there is also a problem that horizontal crosstalk occurs due to voltage fluctuation of the data line 212. This problem will be described in detail as follows.

FIG. 15 is a diagram showing the waveform of the data signal Xj in relation to the scanning signals Yi and Y (i + 1) in the comparison configuration. As shown in this figure, in the comparison configuration, the voltage waveform of the data signal Xj when the pixels in the j column are continuously set to the lowest gradation value G0 is as described above, and the pixels in the j column are continuous. As for the voltage waveform of the data signal in the case of the intermediate gradation value, for example, the gradation value G4, as shown in the figure, the ON voltage having the opposite polarity to the selection voltage is temporally changed in the second half period Tb. The waveform is shifted toward the trailing edge and the off-voltage is shifted toward the leading edge in terms of time. In the first half period, the waveform is inverted in the second half period.
Here, when all the pixels in the i-th row have the gradation value G4, the data signal X1,
X320 is the same as the voltage waveform of the data signal Xj when the gradation value is G4. Therefore, for example, when the positive selection voltage + Vs is applied to the scanning line in the second half period Tb, the off-voltage + Vd is applied to all the data lines of 320 columns from the off voltage + Vd in the middle of the second half period Tb in which the selection voltage + Vd is applied. It will be switched to the on-voltage -Vd at the same time.
On the other hand, half of one pixel line located in the i row is set to the lowest gradation value G0, and the other half is set to the gradation value G.
4, the data signal corresponding to the pixel column having the gradation value G0 is the same as the voltage waveform of the data signal Xj when the gradation value G0 is the lowest, and the pixel signal having the gradation value G4 The corresponding data signal has the same voltage waveform as that of the data signal Xj when the gradation value is G4. For this reason, when the positive selection voltage + Vs is applied to the scanning line in the latter half period Tb, the data line is simultaneously switched from the off voltage + Vd to the on voltage −Vd during the latter half period Tb in which the selection voltage + Vd is applied. Will be halved to 160 columns.

As described above, when the voltage of each data line 212 is switched, the voltage of the scanning line 312 also varies. However, the voltage variation increases as the number of data lines whose voltage is switched at the same timing increases. For this reason, the amount of change in the selection voltage differs between the case where all the pixels for one row have the gradation value G4 and the case where only half of the one pixel row has the gradation value G4. As described above, the gradation actually displayed on the pixel is determined by the selection voltage and the data line voltage during the period in which the selection voltage is applied. Therefore, the difference in the selection voltage directly affects the gradation. become. Specifically, the variation amount of the selection voltage in the case where all the pixels for one row have the gradation value G4 is larger than the variation amount of the selection voltage in the case where only one half of the pixel row has the gradation value G4. Since it increases in the signal voltage switching direction (lowering the positive selection voltage + Vs and increasing the negative selection voltage −Vs), the effective voltage value of the liquid crystal capacitor 118 is reduced. For this reason, in the normally white mode, the gradation value G4 is all for one row of pixels.
In this case, the pixels that are actually displayed become brighter than the pixels that are actually displayed when only half of one pixel row has the gradation value G4.
Note that the change in the selection voltage in the scanning line appears as a change in the gradation value in the horizontal direction.
This is the reason called horizontal crosstalk.

On the other hand, in the present embodiment, as shown in FIG. 8, in the latter half period Tb in which the positive polarity selection voltage + Vs is applied, the data signal Xj in the odd-numbered j columns is set to the trailing edge system, and even (j + 1) )
Since the data signal X (j + 1) in the column is of the leading edge type, the off voltage + Vd in the data signal Xj
To the on-voltage −Vd and the on-voltage − in the data signal X (j + 1)
The switching timing from Vd to off-voltage + Vd is close to each other.
On the other hand, in the latter half period Tb in which the negative selection voltage -Vs is applied, the data signal X in the odd-numbered j columns
Since j is the leading edge method and the even (j + 1) column data signal X (j + 1) is the trailing edge method, the switching timing from the on voltage + Vd to the off voltage −Vd in the data signal Xj and the data In the signal X (j + 1), the switching timing from the off voltage −Vd to the on voltage + Vd is close to each other.
For this reason, in this embodiment, in each scanning line 312, the voltage fluctuation due to the voltage switching of the odd-numbered j-th data line 212 is canceled by the voltage fluctuation due to the voltage switching of the even-numbered (j + 1) -th data line 212. In particular, as a result of suppressing the variation of the selection voltage, it is possible to suppress the occurrence of the above-described lateral crosstalk and make it inconspicuous. Further, for example, when the number of pixels to be set to the gradation value G4 is a majority of the number of rows across a plurality of rows, the influence due to the voltage switching of the odd-numbered data lines 212 and the influence due to the voltage switching of the even-numbered data lines 212 As a result of canceling out, not only the selected voltage but also the fluctuation of the non-selected voltage can be suppressed.
The distortion of the voltage waveform is reduced, and the power consumption can be reduced accordingly.

Furthermore, when attention is paid to the same data line 212, the number of times of voltage switching when the pixel is set to the intermediate gradation is 3 times per horizontal scanning period in the comparison configuration (see FIG. 15).
In the embodiment, since the trailing edge method and the leading edge method are alternately switched every horizontal scanning period, the number is reduced to twice per horizontal scanning period. For this reason, since the power consumed by the capacitance parasitic on the data line 212 is suppressed, the power consumption can be further reduced.
In the present embodiment, the period of taking the voltage + Vd as the data signal and the period of taking the voltage −Vd as the data signal in the horizontal scanning period are 50% regardless of the gradation value. If the influence of the vertical and horizontal crosstalk is not considered, they are constant without depending on the gradation value.

As described above, according to the present embodiment, it is possible to simultaneously eliminate the above-described vertical crosstalk and horizontal crosstalk and to reduce power consumption.

<Application and deformation>
In the embodiment described above, as shown in FIG. 9A, when the positive selection voltage + Vs is applied to the i-th scanning line in the n frame, the odd-numbered j column is the trailing edge method, The even (j + 1) column uses the leading edge method, while the next (i + 1) th scanning line is applied with the negative selection voltage -Vs, and the odd number j column uses the leading edge method. In the row, the trailing edge method is used.
Further, as shown in FIG. 9B, in the next (n + 1) frame, the negative selection voltage -Vs is applied to the i-th scanning line, and the leading edge method is applied to the odd-numbered j columns. Even number (j +
1) In the column, the trailing edge method is used, while in the next (j + 1) th row, the positive polarity selection voltage + Vs is applied. In the odd number j column, the trailing edge method is used, and in the even number (j + 1) column, the leading edge method is used. .
That is, a pixel that has a trailing edge method in positive polarity writing has a leading edge method in negative polarity writing, while a pixel that has a trailing edge method in negative polarity writing has a leading edge method in positive polarity writing. . For this reason, if there is a difference in the effective value of the written voltage between the leading edge method and the trailing edge method for some reason, the liquid crystal capacitor 118 is not correctly driven by alternating current, and a direct current component is applied. Cause flicker.
Therefore, for example, as shown in FIG. 10, in one pixel, four types of positive polarity / rear edge method, negative polarity / leading edge method, positive polarity / leading edge method, negative polarity / rear edge method are used in 4 frames By adopting a circulating configuration, even if there is a difference in the effective value of the voltage written between the leading edge method and the trailing edge method, the liquid crystal capacitor 118 is correctly AC driven if 4 frames are considered as a reference for the effective voltage value. Therefore, it is possible to suppress the deterioration of the liquid crystal and the occurrence of flicker due to the application of the direct current component. The order of circulation is not necessarily the order of a → b → c → d (→ a). For example, a → a → b → b → c → c → d → d (
→ The order of a) may be used.

In the embodiment, the selection voltage is applied in the second half period Tb of the horizontal scanning period. However, as shown in FIGS. 11 and 12, the selection voltage may be applied in the first half period Ta of the horizontal scanning period. . Even in this configuration, vertical crosstalk can be eliminated as shown in FIG. 11, and horizontal crosstalk can also be eliminated as shown in FIG.
In this configuration, in the odd-numbered j columns, the inverted waveform of the first half period Ta to which the selection voltage is applied is applied in the second half period Tb of the same horizontal scanning period. Also, even number (j + 1)
In the column, the inverted waveform of the first half period Ta where the selection voltage is applied is applied in advance to the second half Tb of the preceding horizontal scanning period.
Further, in the embodiment and the application example, the relationship between the odd-numbered columns and the even-numbered columns is changed, and the memory 252
The gradation data read out from the image data may be delayed by 0.5H in the odd columns than in the even columns. Further, instead of accumulating the gradation data Ds in the memory 252, a configuration may be adopted in which a higher-level circuit supplies the gradation data Ds in synchronization with vertical and horizontal scanning in the electro-optical panel 100.

In the embodiment, the configuration in which the TFD element 220 is connected to the data line 212 and the liquid crystal capacitor 118 is connected to the scanning line 312 is illustrated, but conversely, the TFD element 220 is connected.
May be connected to the scanning line 312 and the liquid crystal capacitor 118 may be connected to the data line 212.
Furthermore, in the embodiment, the active matrix type electro-optical device including the TFD element 220 has been exemplified. However, the present invention does not use this type of nonlinear element, and the passive type in which the liquid crystal is sandwiched by the intersection of the strip-shaped electrodes. The present invention can also be applied to a matrix type electro-optical device.
In addition, instead of the normally white mode, when the effective voltage value of the liquid crystal capacitor 118 is small, a normally black mode in which the light transmittance is reduced to display black may be used.

<Electronic equipment>
Next, an electronic apparatus including the electro-optical device according to the invention as a display device will be described.
FIG. 13 is a perspective view illustrating a configuration of a mobile phone having the electro-optical device according to the embodiment.
As shown in this figure, the mobile phone 1200 includes a plurality of operation buttons 1202 operated by a user, a mouthpiece 1204 for outputting a sound received from another terminal device, and a sound transmitted to the other terminal device. In addition to the mouthpiece 1206 for inputting, an electro-optical device for displaying various images is provided. In this figure, the electro-optical panel 10 of the electro-optical device.
Only the 0 display area is shown.

In addition to the mobile phone shown in FIG. 13, examples of electronic devices that can use the electro-optical device according to the present invention include notebook personal computers, liquid crystal televisions, viewfinder type (or monitor direct view type) video recorders. , Digital camera, car navigation system, pager, electronic notebook, calculator, word processor, workstation, videophone, P
Examples include an OS terminal, a device provided with a touch panel, and the like. In any electronic device, it is possible to achieve high-quality display with reduced power consumption while suppressing vertical and horizontal crosstalk.

1 is a diagram illustrating a configuration of an electro-optical device according to an embodiment of the invention. It is a figure which shows the structure of the pixel in the same electro-optical apparatus. It is a figure which shows the voltage waveform of the scanning signal in the same electro-optical apparatus. FIG. 3 is a diagram illustrating a configuration of a data line driving circuit in the electro-optical device. It is a figure which shows the voltage waveform of the data signal in the data line drive circuit. It is a figure which shows the voltage waveform of the data signal in the data line drive circuit. It is a figure which shows suppression of the longitudinal crosstalk in the same electro-optical apparatus. It is a figure which shows suppression of the horizontal crosstalk in the same electro-optical apparatus. It is a figure which shows the drive system of the same electro-optical apparatus. It is a figure which shows the drive system of the electro-optical apparatus which concerns on the application example of this invention. It is a figure which shows the voltage waveform of the data signal which concerns on the application example of this invention. It is a figure which shows the voltage waveform of the data signal which concerns on the application example of this invention. It is a figure which shows the structure of the mobile telephone to which the same electro-optical apparatus is applied. It is a figure which shows the voltage waveform of the data signal which concerns on a prior art example. It is a figure which shows the voltage waveform of the data signal which concerns on a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Electro-optical device, 100 ... Electro-optical panel, 116 ... Pixel, 118 ... Liquid crystal capacity, 1
19 ... pixel electrode, 220 ... TFD element, 212 ... data line, 250 ... data line drive circuit,
312 ... Scanning line 350 ... Scanning line drive circuit 400 ... Control circuit 450 ... Gradation control pulse generation circuit 500 ... Voltage generation circuit 1200 ... Cell phone

Claims (10)

A driving method of an electro-optical device for driving a plurality of pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
In the latter half of the horizontal scanning period, a positive voltage and a negative voltage are alternately applied to the reference voltage,
In the second half of each horizontal scanning period,
When applying one of the positive or negative selection voltage,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
A predetermined on-voltage is applied in the latter half of the period corresponding to the gray level of the pixel to which the selection voltage is applied, and the predetermined on-voltage is applied in the latter half of the period in which the on-voltage is not applied. In the first half period of the horizontal scanning period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance.
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied forward in the second half period by a period corresponding to the gradation of the pixel to which the selection voltage is applied, and the off-voltage is applied in the second half period in which the on-voltage is not applied. While applying a voltage and applying a waveform in which the on-voltage and the off-voltage in the second half period are switched in the first half period of the horizontal scanning period next to the horizontal scanning period,
When applying the other selection voltage of the positive or negative polarity,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
The on-voltage is applied forward in the second half period by a period corresponding to the gradation of the pixel to which the selection voltage is applied, and the off-voltage is applied in the second half period in which the on-voltage is not applied. A voltage is applied, and in the first half period of the horizontal scanning period, a waveform in which the on voltage and the off voltage in the second half period are switched is applied in advance,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied while being shifted backward in the second half period by a period corresponding to the gradation of the pixel to which the selection voltage is applied, and the off-voltage is applied in the second half period in which the on-voltage is not applied. An electro-optical device characterized by applying a voltage and applying a waveform in which the on-voltage and the off-voltage in the second half period are switched in the first half period of the horizontal scanning period next to the horizontal scanning period. Driving method. A driving method of an electro-optical device for driving a plurality of pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
In the latter half of the horizontal scanning period, a positive voltage and a negative voltage are alternately applied to the reference voltage,
In the first half of each horizontal scanning period,
When applying one of the positive or negative selection voltage,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
A predetermined on-voltage is applied while being shifted backward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied in the first half period, and is predetermined in the period in which the on-voltage is not applied in the first half period. And applying a waveform in which the on voltage and the off voltage in the first half period are switched in the second half of the horizontal scanning period,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the first half period by a period corresponding to the gradation of the pixel to which the selection voltage is applied, and the off-voltage is applied in the first half period in which the on-voltage is not applied. In the second half of the horizontal scanning period prior to the horizontal scanning period, a voltage is applied in advance, and a waveform in which the on voltage and the off voltage in the first half period are switched is applied in advance.
When applying the other selection voltage of the positive or negative polarity,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the first half period by a period corresponding to the gradation of the pixel to which the selection voltage is applied, and the off-voltage is applied in the first half period in which the on-voltage is not applied. Voltage is applied, and in the second half of the horizontal scanning period, a waveform in which the on voltage and the off voltage in the second half period are switched is applied,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied behind the period of time corresponding to the gradation of the pixel to which the selection voltage is applied in the first half period, and the off-voltage is applied in the period in which the on-voltage is not applied in the first half period. An electro-optical device, wherein a voltage is applied and a waveform in which the on-voltage and the off-voltage in the first half period are switched is applied in advance in the second half of the horizontal scanning period before the horizontal scanning period. Driving method. For one pixel,
A first frame that brings the on-voltage backward in time in a period in which the positive selection voltage is applied;
A second frame that brings the on-voltage forward in time during a period in which the negative selection voltage is applied;
A third frame that brings the on-voltage forward in time during the period of applying the positive selection voltage;
3. The electro-optical device according to claim 1, wherein, in a period in which the negative selection voltage is applied, the fourth frame in which the ON voltage is moved backward in time is repeated in a predetermined order. Driving method. A driving method of an electro-optical device for driving a plurality of pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
In the latter half of the horizontal scanning period, a positive voltage and a negative voltage are alternately applied to the reference voltage,
In the second half of each horizontal scanning period,
When applying one of the positive or negative selection voltage,
When a first gradation is designated for a pixel belonging to one of an odd column and an even column among the plurality of data lines, a positive or negative data voltage with respect to the reference voltage is selected for the data line. Apply a data voltage having a polarity opposite to the selection voltage to be applied from the start point to the end point of the latter half period,
When a second gradation different from the first gradation is designated, a data voltage having the same polarity as the selection voltage to be applied is applied to the data line from the start point to the end point of the latter half period. ,
In addition, an inverted waveform of the data voltage applied in the latter half period is applied in advance from the start point to the end point of the first half period of the horizontal scanning period,
When the first gradation is designated for pixels belonging to the other of the odd and even columns among the plurality of data lines, a data voltage having a polarity opposite to the selection voltage to be applied is applied to the data line. Applied from the beginning to the end of the period,
When the second gradation is designated, a data voltage having the same polarity as the selection voltage to be applied is applied to the data line from the start point to the end point of the latter half period,
An inversion waveform of the data voltage applied in the second half period is applied from the start point to the end point of the first half period of the horizontal scanning period next to the horizontal scanning period. . A driving method of an electro-optical device for driving a plurality of pixels arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
In the latter half of the horizontal scanning period, a positive voltage and a negative voltage are alternately applied to the reference voltage,
In the first half of each horizontal scanning period,
When applying one of the positive or negative selection voltage,
When a first gradation is designated for a pixel belonging to one of an odd column and an even column among the plurality of data lines, a positive or negative data voltage with respect to the reference voltage is selected for the data line. Applying a data voltage having the opposite polarity to the selection voltage to be applied from the start point to the end point of the first half period,
When a second gradation different from the first gradation is designated, a data voltage having the same polarity as the selection voltage to be applied is applied to the data line from the start point to the end point of the first half period. ,
In addition, an inverted waveform of the data voltage applied in the first half period is applied from the start point to the end point of the second half period of the horizontal scanning period,
When the first gradation is designated for pixels belonging to the other of the odd and even columns among the plurality of data lines, a data voltage having a polarity opposite to the selection voltage to be applied is applied to the data line. Applied from the beginning to the end of the period,
When the second gradation is specified, a data voltage having the same polarity as the selection voltage to be applied is applied to the data line from the start point to the end point of the first half period,
In addition, the inversion waveform of the data voltage applied in the first half period is applied in advance from the start point to the end point of the second half period of the horizontal scanning period before the horizontal scanning period. Method. A drive circuit for an electro-optical device in which a plurality of pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
A scanning line driving circuit that alternately applies positive and negative selection voltages to a reference voltage in the second half of the horizontal scanning period;
In the second half of each horizontal scanning period,
When one of the positive polarity and the negative polarity selection voltage is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
A predetermined on-voltage is applied backward in time in a period corresponding to the gradation of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. A predetermined off voltage is applied, and in the first half period of the horizontal scanning period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance.
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the period corresponding to the gray level of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. While applying an off voltage and applying a waveform in which the on voltage and the off voltage in the second half period are switched in the first half period of the next horizontal scanning period of the horizontal scanning period,
When the other selection voltage of the positive polarity or the negative polarity is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the period corresponding to the gray level of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. An off voltage is applied, and in the first half of the horizontal scanning period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied while being shifted backward in time in a period corresponding to the gradation of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. A data line driving circuit that applies an off voltage and applies a waveform in which the on voltage and the off voltage in the second half period are switched in the first half period of the next horizontal scanning period of the horizontal scanning period;
A drive circuit for an electro-optical device, comprising: A drive circuit for an electro-optical device in which a plurality of pixels are arranged corresponding to each intersection of a plurality of scanning lines and a plurality of data lines,
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
A scanning line driving circuit that alternately applies positive and negative selection voltages to the reference voltage in the first half of the horizontal scanning period;
In the first half of each horizontal scanning period,
When one of the positive polarity and the negative polarity selection voltage is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
In the first half period, a predetermined on-voltage is applied backward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. Apply a predetermined off voltage, and in the second half of the horizontal scanning period, apply a waveform in which the on voltage and the off voltage in the first half period are switched,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied while being moved forward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. While applying an off voltage and pre-applying a waveform in which the on voltage and the off voltage in the first half period are switched in the second half of the horizontal scanning period before the horizontal scanning period,
When the other selection voltage of the positive polarity or the negative polarity is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied while being moved forward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. Apply an off voltage, and in the second half of the horizontal scanning period, apply a waveform in which the on voltage and the off voltage in the second half period are switched,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied backward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. A data line driving circuit that applies an off-voltage and applies in advance a waveform in which the on-voltage and the off-voltage in the first half period are switched in the second half of the horizontal scanning period before the horizontal scanning period;
A drive circuit for an electro-optical device, comprising: A plurality of pixels arranged corresponding to each intersection of the plurality of scanning lines and the plurality of data lines;
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
A scanning line driving circuit that alternately applies positive and negative selection voltages to a reference voltage in the second half of the horizontal scanning period;
In the second half of each horizontal scanning period,
When one of the positive polarity and the negative polarity selection voltage is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
A predetermined on-voltage is applied backward in time in a period corresponding to the gradation of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. A predetermined off voltage is applied, and in the first half period of the horizontal scanning period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance.
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the period corresponding to the gray level of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. While applying an off voltage and applying a waveform in which the on voltage and the off voltage in the second half period are switched in the first half period of the next horizontal scanning period of the horizontal scanning period,
When the other selection voltage of the positive polarity or the negative polarity is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
The on-voltage is applied by moving forward in the period corresponding to the gray level of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. An off voltage is applied, and in the first half of the horizontal scanning period, a waveform obtained by switching the on voltage and the off voltage in the second half period is applied in advance,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
The on-voltage is applied while being shifted backward in time in a period corresponding to the gradation of the pixel to which the selection voltage is applied in the latter half period, and the on-voltage is not applied in the latter half period. A data line driving circuit that applies an off voltage and applies a waveform in which the on voltage and the off voltage in the second half period are switched in the first half period of the next horizontal scanning period of the horizontal scanning period;
An electro-optical device comprising: A plurality of pixels arranged corresponding to each intersection of the plurality of scanning lines and the plurality of data lines;
The plurality of scanning lines are selected row by row for each horizontal scanning period, and the selected scanning lines are
A scanning line driving circuit that alternately applies positive and negative selection voltages to the reference voltage in the first half of the horizontal scanning period;
In the first half of each horizontal scanning period,
When one of the positive polarity and the negative polarity selection voltage is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
In the first half period, a predetermined on-voltage is applied backward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. Apply a predetermined off voltage, and in the second half of the horizontal scanning period, apply a waveform in which the on voltage and the off voltage in the first half period are switched,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied while being moved forward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. While applying an off voltage and pre-applying a waveform in which the on voltage and the off voltage in the first half period are switched in the second half of the horizontal scanning period before the horizontal scanning period,
When the other selection voltage of the positive polarity or the negative polarity is applied,
For data lines belonging to one of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied while being moved forward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. Apply an off voltage, and in the second half of the horizontal scanning period, apply a waveform in which the on voltage and the off voltage in the second half period are switched,
For data lines belonging to the other of the odd or even columns among the plurality of data lines,
In the first half period, the on-voltage is applied backward in time for a period corresponding to the gradation of the pixel to which the selection voltage is applied, and in the first half period in which the on-voltage is not applied. A data line driving circuit that applies an off-voltage and applies in advance a waveform in which the on-voltage and the off-voltage in the first half period are switched in the second half of the horizontal scanning period before the horizontal scanning period;
An electro-optical device comprising:   An electronic apparatus comprising the electro-optical device according to claim 8.

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