JPH05158442A - Driving method for liquid crystal display device and liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide a driving method for a liquid crystal panel by which the irregularity of brightness(crosstalk) in a liquid crystal display device is prevented from occurring and the liquid crystal display device provided with a driving device which is directly used in order to execute this driving method. CONSTITUTION:This device is provided with a liquid crystal panel 3, a data driver 1 which selectively impresses voltage on data electrodes X1-Xn, a scanning driver 2 which selectively impresses the voltage on scanning electrodes Y1-Ym, a liquid crystal display control means 8 which outputs a liquid crystal display signal, an arithmetic circuit 5 which subtracts the number of cells where display data is not changed from the display data just before in every scanning electrode from the number of cells where it is changed, a polarity inverted signal output circuit 6 which outputs an inverted signal only when the output from the circuit 5 is positive, and an exclusive OR gate 7 which outputs the inverted signal by exclusively ORing a frame signal Df and the signal of the circuit 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved driving method for a liquid crystal panel having a simple matrix structure and a liquid crystal display device having a driving device directly used for implementing the improved driving method. In particular, the present invention relates to a method for driving a liquid crystal panel capable of preventing the occurrence of uneven brightness (crosstalk) in a liquid crystal display device, and an improvement aimed at providing the liquid crystal display device.

[0002]

2. Description of the Related Art In recent years, with the spread of personal computers, word processors, etc., CRTs having large size and large power consumption as their display devices.
In place of the above, the adoption of a light-weight, battery-operable liquid crystal display device has become remarkable. Liquid crystal display devices are roughly divided into a simple matrix type and an active matrix type, but the active matrix type is difficult to manufacture because a non-linear element is required for each pixel. The device generally employs a simple matrix structure.

Hereinafter, a conventional liquid crystal display device having a simple matrix structure and a driving method thereof will be described with reference to the drawings. FIG. 4 is a configuration diagram of a liquid crystal display device having a simple matrix structure according to the related art. In the figure, 1 is
Based on the input display data signal SX of the liquid crystal display panel 3, one of the plurality of voltages supplied from the power supply circuit 4 is selected and sequentially applied to each of the data electrodes X _n of the liquid crystal display panel 3. It is a data driver. 2 is
A scan driver that selects one of the plurality of voltages supplied from the power supply circuit 4 based on the input scan signal SY of the liquid crystal display panel and sequentially applies it to each of the scan electrodes Y _m of the liquid crystal display panel 3. is there. A liquid crystal display 8 outputs a display data signal SX to the data driver 1 and a scan signal SY to the scan driver 2 based on a command from a control circuit (not shown) such as a personal computer. It is a control means.

Next, a method of driving the liquid crystal display device will be described. For example, in the case of the display shown in FIG. 5, when all the X ₁ columns of the liquid crystal panel are written “bright” (the liquid crystal display is transparent (hereinafter referred to as “light”)), the data electrodes of the X ₁ column are not displayed. When the data voltage shown by the solid line in FIG. 6 (a) is applied and all the X ₂ columns of the liquid crystal panel are written "dark" (the liquid crystal display is cloudy (hereinafter referred to as dark)), the data of the X ₂ column is written. The data voltage shown by the broken line in FIG. 6A is applied to the electrodes. Then, the scan voltage shown in FIG. 6B is applied to the scan electrode of the Y ₁ row of the liquid crystal panel, and the scan voltage shown in FIG. 6C is applied to the scan electrode of the Y ₂ row of the liquid crystal panel. .. As a result, the liquid crystal cell α (see FIG. 5 again)
6D is applied with the cell voltage indicated by the solid line in FIG. 6D, and the liquid crystal cell β (see FIG. 5 again) is applied with the cell voltage indicated by the broken line in FIG. 6D. In addition, the first cycle shown in FIG.
The second period is for the purpose of preventing the deterioration of panel characteristics.
This is a cycle for applying the voltage shown in FIG. 7 for the same period so that no DC voltage component is applied to the liquid crystal cell.

[0005]

[SUMMARY OF THE INVENTION Incidentally in the above prior art, a row at a certain time T ₁ (e.g., Y ₁
Display of the three liquid crystal cells A~C lines) is "dark dark", consider the case of changes as the "KuraAkiraAkira" at time T _2. At this time, since the liquid crystal panel has the electrode resistance R and the liquid crystal cell capacitance C, the equivalent circuit of the Y ₁ row is as shown in FIG. Then, when changing from a certain time T ₁ to a time T ₂ , of the data electrodes X _{1 to} X ₃ , the data electrode X ₂
・ The voltage of X ₃ changes from (2 / a) V to 0, and
-The potential at point c instantaneously becomes-(1 / a) V. on the other hand,
The potential of the data electrode X ₁ changes from 0 to (2 / a) V,
The potential at point a in FIG. 8 instantaneously becomes (3 / a) V. However, since the number of bright and dark liquid crystal cells is different, the voltage (1 / a) V of the scan electrode Y ₁ is pulled to − (1 / a) V. Therefore, when the time T ₁ changes to the time T ₂ , the voltage of the scan electrode Y ₁ changes as shown in FIG.

As a result of such differential pulse appearing in the scan voltage, the voltage waveform (X _1-
Y ₁ ) and the voltage waveform (X ₂ −
Y ₁ ) has a problem that the edge is blunted or lifted.

This problem will be described with a specific example. For example, if there is a 3 × 3 dot liquid crystal display panel and it has the display pattern shown in FIG. 10, paying attention to the drive waveforms of the cells A and B in the first row, the above-mentioned cells A and B are displayed.
Voltage waveform of the data electrodes X ₁ · X ₂ constituting the scan electrode Y ₁ and the cell A · B is as shown in FIG. As can be seen from FIG. 11, there is a difference in the effective value of the cell voltage between the cell A and the cell B while writing to the “bright” state, which causes a luminance difference (the cell A is brighter), that is, a so-called cross. Talk occurs.

Next, consider a case where the display "brightness / darkness" of the liquid crystal cells A to C in the Y ₁ row at a certain time T ₁ does not change at the time T ₂ but the polarity is reversed. In this case, when the time T ₁ changes to a time T ₂ , the voltage of X ₂ · X ₃ among the data electrodes X _{1 to} X ₃ is (2 / a) V to [1- (2 / a)]. The voltage changes to V and the voltage of [1- (3 / a)] V is instantaneously applied to the scan electrode Y ₁ . The data electrode X ₁ changes from 0 to V,
The voltage of [1+ (1 / a)] V is instantaneously applied to the scan electrode Y.
It is applied to _1, but the voltage of the scan electrodes Y ₁ because there is a difference in the number of liquid crystal cells of the light-dark [1- (1 / a)] V is [1- (3
/ A)] V. Therefore, when the time T ₁ changes to the time T ₂ , the voltage of the scan electrode Y ₁ changes as shown in FIG.

As a result of such differential pulses appearing in the scan voltage, the voltage waveform (X _1-
Y ₁ ) and the voltage waveform (X ₂ −
Y ₁ ) still has the problem that the edge is blunted or lifted.

This problem will also be described with a concrete example. For example, if there is a liquid crystal display panel of 3 × 3 dots and it has a display pattern as shown in FIG. 13, paying attention to the drive waveforms of the cells A and B in the first row, the data forming those cells Electrodes X ₁ and X ₂ and scan electrode Y
The voltage waveforms of ₁ and cells A and B are as shown in FIG. As can be seen from FIG. 14, there is a difference in the effective value of the cell voltage between the cell A and the cell B while writing to the “bright” state, which causes a difference in luminance (cell A is brighter),
So-called crosstalk still occurs.

As described above, in the prior art, when the display data on the scan electrodes changes from a certain time T ₁ to a certain time T ₂ , the number of liquid crystal cells changing from “bright” to “dark” and “dark”. Crosstalk occurs when there is a difference in the number of liquid crystal cells changing from "to" to "bright", and the display data does not change at the time of transition from time T ₁ to time T ₂ and is displayed when the polarity is reversed. When there is a difference in the number of "bright" and "dark" data, crosstalk occurs and the display quality deteriorates.

An object of the present invention is to eliminate the above-mentioned drawbacks, and a method for driving a liquid crystal panel capable of preventing the occurrence of luminance unevenness (crosstalk) in a liquid crystal display device and a method for directly implementing the driving method. An object of the present invention is to provide a liquid crystal display device having a driving device used.

[0013]

The above object can be achieved by the following liquid crystal display driving method and liquid crystal display.

In the method of driving a liquid crystal display device, a liquid crystal is provided between a plurality of intersecting data electrodes (X _n ) and a scan electrode (Y _m ) to arrange a plurality of liquid crystal cells in a matrix, and the data electrodes (X _n ) And a scan electrode (Y _m ) are applied to the liquid crystal display device for driving the liquid crystal cell by applying a voltage for on-display or off-display in a combined form and inverting the polarity at a selected cycle. In the method, the polarity inversion is performed when the subtraction result obtained by subtracting the data non-inversion number from the data inversion number is positive, the polarity inversion is not performed when the subtraction result is negative, and the selection and non-selection are performed on the data electrode (X _n ). in the driving method of the liquid crystal display device to reduce the effective voltage value of the differential-shaped pulses induced in the scan electrode (Y _m) which face each other with a capacitance having a liquid crystal cell upon application of a pulse voltage That.

In the above structure, the voltage (V) is applied to the selected scan electrode (Y _m ) with respect to the voltage applied to the selected data electrode (X _n ) for the liquid crystal cells arranged in matrix. Then, a voltage of 2 / a times the voltage (V) is applied to the unselected data electrode (X _n ) and a voltage of 1 / a times the voltage (V) is applied to the unselected scan electrode (Y _m ). Based on the voltage applied to the selected data electrode (X _n ) and the positive voltage application mode period in which the voltage is applied, an inversion voltage of the voltage (V) is applied to the selected scan electrode (Y _m ), A voltage that is 2 / a times the inversion voltage of the voltage (V) is applied to the unselected data electrode (X _n ), and 1 / a of the inversion voltage of the voltage (V) is applied to the unselected scan electrode (Y _m ). Same as negative voltage application mode period for applying voltage a times It repeated period at a time may be ゝ.

Further, in the above structure, when a plurality of liquid crystal cells corresponding to the respective scan electrodes (Y _m ) are selectively driven, a liquid crystal cell corresponding to one of the scan electrodes (Y _m ) is driven. Each of the multiple display data of
The display data selected immediately before (the scan electrode (Y
_m ) and one of the data electrodes (X _n ) intersecting the scan electrode (Y _m ) and the number of cells changing from the respective display data of the liquid crystal cell). (Y _m) each of the plurality of display data of the liquid crystal cell corresponding to one intersects one of the display data selected immediately before (the scan electrodes (Y _m) and the scan electrode (Y _m) Data electrode (X
_It is advisable to subtract the number of cells that do not change from the respective display data of the liquid crystal cells configured with _n ) and to execute the polarity inversion only when the subtraction result is positive.

A liquid crystal display device which achieves the object of the present invention.
The device may be any of the following. First liquid crystal display device
Is a plurality of intersecting data electrodes (X_n) And scan electrodes
(Y_m) And the liquid crystal is enclosed between
A liquid crystal display panel (3) in which the components are arranged in a matrix,
The data electrode (X_n) Selected and unselected pulse
A data driver (1) for selecting and applying a voltage;
Scan electrode (Y _m) Selected and unselected pulsed
The scan driver (2) that selects and applies the pressure, and
The drivers (1) and (2) are provided with the selection voltage and the non-selection voltage.
Of a liquid crystal display device having a power supply circuit (4) for supplying
In a liquid crystal display device having a moving device, the scan
Electrode (Y_m) Multiple display data of the liquid crystal cell corresponding to one of
Each of the
Scan electrode (Y_m) And this scan electrode (Y
_m) And the data electrode (X_n) With each
(Display data for each of the above liquid crystal cells)
From the number of cells changing from the scan electrode
(Y_mDisplay data of liquid crystal cell corresponding to one of
Of the display data selected immediately before
Can electrode (Y_m) And this scan electrode (Y_m)
Data electrode (X_n) With each
Display data of each of the above liquid crystal cells)
An arithmetic circuit (5) for subtracting the number of unchanged cells, and
The inverted signal is output only when the output of the arithmetic circuit (5) is positive.
Liquid crystal display having polarity inversion signal output circuit (6)
It is a device.

The second liquid crystal display device uses the voltage applied to the selected data electrode (X _n ) as a reference for the liquid crystal cells arranged in a matrix, and the selected scan electrode (Y).
Voltage (V) is applied to _m), 2 / the a times voltage is applied, the scan electrodes that are not selected (Y _m) to said voltage of the data electrodes that are not selected (X _n) to said voltage (V) ( V) and a means for determining a positive voltage application mode period for applying a voltage of 1 / a times, and a voltage applied to the selected data electrode (X _n ) as a reference, and the selected scan electrode (Y
_m ) is applied with an inversion voltage of the voltage (V), and 2 / of the inversion voltage of the voltage (V) is applied to the unselected data electrode (X _n ).
applying a a multiple of the voltage, means for determining a negative voltage application mode period for applying the 1 / a times the voltage of the inverting voltage of the scan electrodes that are not selected (Y _m) above the voltage (V),
A liquid crystal display device having means for applying the positive voltage application mode period and the negative voltage application mode period for the same period.

[0019]

According to the present inventor, the cause of crosstalk in the prior art is when the display data changes (from "bright" to "dark" or from "dark" to "bright") or when the display data changes. When the polarity is reversed without doing so, the scan voltage is transiently changed by being affected by the voltage change of the data electrode.Therefore, the display panel driving method that the scan voltage is not affected by the voltage change of the data electrode is used. The present invention has been made on the idea that crosstalk can be prevented.

The operation of the present invention will be described in detail below.
First, in the above-mentioned crosstalk occurrence example, the display data is
Time T₁To T₂Scan electrode Y when changing to
₁The number of data displayed above changes from "bright" to "dark"
If there is a difference in the number of changes from “dark” to “bright”,
Tick T₁To T₂What happens if you reverse the polarity when changing to
Consider whether or not. Same as the previous Y₁3 liquid crystal cells A per row
There is ~ C, time T₁The display "bright and dark" at time T
₂When changing like "dark and bright" in
Then, as shown in FIG. 2, the data electrode X₂The potential of
(2 / a) V changes to V (data electrode X₃Data
Electrode X ₂Changes as well. ), And the data electrode X₁
Voltage changes from 0 to [1- (2 / a)] V, and
Scan electrode Y₁Voltage from (1 / a) V to [1- (1
/ A)] V. Therefore, time T₁From time
T₂Scan electrode Y when changing to₁Change in voltage
Is [1- (2 / a)] V, and changes in the voltage of the data electrode
The conversion amount is also [1- (2 / a)] V, and the scan electrode Y₁
Change of the voltage of the same as the change of the voltage of the data electrode
Therefore, scan electrode Y₁Voltage of the data electrode
As shown in Fig. 2, it does not change transiently under the influence of
Scan electrode Y₁The differential pulse is present in the voltage of
No crosstalk will occur.

Next, it will be examined what happens if the display data does not change when the time T ₁ changes to the time T ₂ and the polarity is inverted, but the polarity is not inverted. Similar to the previous example, there are three liquid crystal cells A to C in the Y ₁ row and the time T
When the display in _one "dark dark" is not changed at time T _2,, data electrodes X ₁ voltage and voltage of the scan electrodes Y ₁ of to X ₃ are both varied as time T ₁ and time T _2, it is not, respectively The voltage is as shown in Fig. 3 (data electrode X
₁ and X ₂ only).

That is, when the time T ₁ changes to the time T ₂ , the voltage applied to the liquid crystal cells A to C does not change, so that the differential pulse does not appear in the voltage of the scan electrode Y ₁ .
Crosstalk does not occur.

As described above, when the display data on the scan electrode changes from a certain time T ₁ to a certain time T ₂ , the number of liquid crystal cells changing from “bright” to “dark” and the change from “dark” to “bright”. If there is a difference in the number of liquid crystal cells
When changing from ₁ to time T ₂ , polarity inversion is performed.
When there is no change in the display data when changing from ₁ to time T _2, and when there is a difference in the number of “bright” and “dark” of the display data, polarity inversion is performed when changing from time T ₁ to time T ₂ . If not provided, the differential pulse does not appear and crosstalk does not occur.

In order to correspond to any display pattern based on the above theory, the present invention subtracts the number of cells in which the display data does not change from the number of cells in which the display data changes, and inverts the polarity if the operation result is positive. If it is negative, the drive is performed without polarity inversion.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display driving method and a liquid crystal display according to an embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes a data driver for selecting and applying a selected and non-selected pulse voltage to the data electrode X _n based on an input display data signal SX of a liquid crystal display panel (described later). Reference numeral 2 denotes a scan driver that selects and applies a selected and non-selected pulse voltage to the scan electrode Y _m based on an input scan signal SY of a liquid crystal display panel (described later). 3 is a liquid crystal display panel between a plurality of data electrodes X _n and the scan electrode Y _m crossing have liquid crystal is sealed to form a plurality of liquid crystal cells in a matrix. Reference numeral 4 denotes a voltage V (V _{0 in the} drawing), 0 (V _{5 in the} drawing) and a non-selected voltage [1- (2 / a)] V (V _{2 in the} drawing), ( 2 / a)
V (V _{3 in the} figure) is supplied to the scan driver 2, and the selected voltage V (V _{0 in the} figure), 0 (V _{5 in the} figure) and the non-selected voltage [1- (1 / a)] V (in the figure) V ₁ ), (1 / a) V (V _{4 in the} figure). In the case of the present embodiment, the selection voltage from the data driver 1 causes the "bright" write state, and the non-selection voltage causes the "dark" write state.
5 is a display data signal SX corresponding to a scan electrode
Is an arithmetic circuit for subtracting the number of unchanged cells from the number of changed cells from the display data signal SX of the liquid crystal cell intersecting the same data electrode on the scan electrode selected immediately before.
Reference numeral 6 denotes a polarity inversion signal output circuit which outputs an inversion signal only when the output of the arithmetic circuit 5 is positive. Reference numeral 7 denotes a frame signal output from a liquid crystal display control means (described later) 8 and a signal DF whose polarity is inverted every time data of one frame (one screen) of the liquid crystal panel is sent and the polarity inversion signal output circuit 6 described above. It is an exclusive OR gate that outputs an inversion signal only when the polarity inversion signal output circuit 6 takes an exclusive OR. Reference numeral 8 denotes a liquid crystal display control means, which sends a display data signal SX to the data driver 1 based on a command from a control circuit (not shown) such as a personal computer.
To output the scan signal SY to the scan driver 2, output the cells in which the display data signal SX changes and the cells in which the display data signal SX does not change to the arithmetic circuit 5, and set the frame signal DF to the above exclusion. Output to the logical OR gate 7.

Next, a method of driving the liquid crystal display device will be described. When the display data signal is output from the liquid crystal display control means 8 to the data driver 1 and the scan signal is output to the scan driver 2, the data driver 1 and the scan driver 2 are supplied from the power supply circuit 4 to each of them based on these signals. One of the above voltages is selected and applied to the data electrode X _n and the scan electrode Y _m . In other words, in the positive voltage application mode in which the liquid crystal panel 3 is driven by the positive voltage, the data driver 1
Is the voltage V for the data electrode selected based on the display data signal, and the voltage [1-
(2 / a)] V is applied, while the scan driver 2
Is 0 for scan electrodes selected based on the scan signal, and voltage [1- (1 /
a)] V is applied.

Similarly, in the negative voltage application mode in which the liquid crystal panel 3 is driven with a negative voltage, the data driver 1
Applies 0 to the selected data electrode and a voltage (2 / a) V to the unselected data electrode, while the scan driver 2 applies the voltage V to the selected scan electrode and the unselected scan electrode. Applies a voltage (1 / a) V.

Further, the liquid crystal display control means 8 outputs the above frame signal DF every time one frame (one screen) of data of the liquid crystal panel 3 is transmitted, and this signal is output to the above arithmetic circuit 5. The data is input to the data driver 1 and the scan driver 2 via the output of the polarity inversion signal output circuit 6 which outputs the polarity inversion signal in response and the exclusive OR gate. The data driver 1 and the scan driver 2 are set to either the positive voltage application mode or the negative voltage application mode according to the output DF1 of the exclusive OR gate.

The arithmetic circuit 5 subtracts the number of unchanged cells from the number of cells in which the display data changes, based on the information that the liquid crystal display control means 8 outputs the cells in which the display data for each scan electrode changes and the cells in which the display data does not change. Then, when the operation result is positive, H is output to the polarity inversion signal output circuit 6, and when it is negative, L is output to the polarity inversion signal output circuit 6. The polarity inversion signal output circuit 6 inverts the polarity of DF1 when the output from the arithmetic circuit 5 is H, and does not invert it when it is L.

The polarity inversion signal DF output from the liquid crystal display control means 8 has its polarity inverted every frame (one screen) as described above, and the exclusive OR gate outputs the DF and the polarity inversion signal output circuit. By taking the exclusive OR of DF1 to prevent application of a DC component to the liquid crystal cell.

[0032]

As described above, in the driving method of the liquid crystal display device according to the present invention, the display data of the liquid crystal cell is changed from the number of cells which changes from the display data selected immediately before for each scan electrode of the liquid crystal panel. The number of cells that do not change is subtracted, and the polarity of the voltage applied to the liquid crystal cell is inverted only when the result of the subtraction is positive. Further, the liquid crystal display device according to the present invention includes a liquid crystal panel and a data electrode. A data driver for selecting and applying a voltage based on the display data signal, a scan driver for selecting and applying a voltage based on the scanning signal to the scan electrodes, and a liquid crystal display control means for outputting a signal for controlling the liquid crystal display, An arithmetic circuit for subtracting the number of unchanged cells from the number of cells whose display data corresponding to the scan electrode is changed from the display data selected immediately before, and this operation time. The polarity inversion signal output circuit that outputs an inversion signal only when the output of is positive, and the frame signal output by the liquid crystal display control means and the output of the polarity inversion signal output circuit are exclusive ORed to obtain an inversion signal. Since it has an exclusive OR gate for outputting, the voltage of the scan electrode is affected by the change of the voltage of the data electrode even when the display data of the liquid crystal panel changes or the display data does not change. As a result, the differential pulse does not appear in the voltage of the scan electrode and crosstalk does not occur.

Therefore, according to the present invention, a liquid crystal display device having a driving method of a liquid crystal panel capable of preventing the occurrence of luminance unevenness (crosstalk) in the liquid crystal display device and a driving device directly used for carrying out the driving method. Can be provided.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a voltage waveform diagram (when the display data changes) in the liquid crystal display device of the present invention.

FIG. 3 is a voltage waveform diagram (when display data does not change) in the liquid crystal display device of the present invention.

FIG. 4 is a configuration diagram of a liquid crystal display device according to a conventional technique.

FIG. 5 is an explanatory diagram of a liquid crystal display example.

FIG. 6 is a voltage waveform diagram in a first cycle and a second cycle of the liquid crystal display device.

FIG. 7 is a table of voltage values in the first cycle and the second cycle.

FIG. 8 is an equivalent circuit diagram of a scan electrode Y ₁ row.

FIG. 9 is a voltage waveform diagram (when the display data changes) in the conventional liquid crystal display device.

FIG. 10 is an explanatory diagram of a liquid crystal display example.

11 is a voltage waveform diagram in FIG. 10.

FIG. 12 is a voltage waveform diagram (when display data does not change) in the liquid crystal device of the related art.

FIG. 13 is an explanatory diagram of a liquid crystal display example.

FIG. 14 is a voltage waveform diagram in FIG. 13.

[Explanation of symbols]

1 data driver 2 scan driver 3 liquid crystal display panel 4 power supply circuit 5 arithmetic circuit 6 polarity inversion signal output circuit 7 exclusive OR gate 8 liquid crystal display control means X _n data electrode Y _m scan electrode SX display data signal SY scan signal DF frame signal

Claims (5)

[Claims] 1. A liquid crystal is provided between a plurality of intersecting data electrodes (X _n ) and scan electrodes (Y _m ) to arrange a plurality of liquid crystal cells in a matrix, and the data electrodes (X _n ) and scan electrodes (Y _m). In the driving method of the liquid crystal display device for driving the liquid crystal cell by applying a voltage for on-display or off-display in a combined format and inverting the polarity at a selected cycle from When the subtraction result obtained by subtracting the non-inversion number of data is positive, polarity inversion is performed, when it is negative, polarity inversion is not performed, and when the selected and unselected pulse voltages are applied to the data electrode (X _n ), the polarity inversion is performed. A method for driving a liquid crystal display device, which reduces an effective voltage value of a differential pulse induced in a scan electrode (Y _m ) facing each other through a capacitance of a liquid crystal cell. 2. A liquid crystal cell arranged in a matrix,
With respect to the voltage applied to the data electrodes selected (X _n), by applying a voltage (V) to the scan electrodes (Y _m) to be selected, the voltage on the data electrodes are not selected (X _n) of (V) A positive voltage application mode period in which a voltage of 2 / a times is applied and a voltage of 1 / a times the voltage (V) is applied to the unselected scan electrode (Y _m ) and the selected data electrode (X _n ). The voltage applied to the reference voltage is applied as a reference, and an inversion voltage of the voltage (V) is applied to the selected scan electrode (Y _m ),
A voltage that is 2 / a times the inversion voltage of the voltage (V) is applied to the unselected data electrode (X _n ) and 1 / a times the inversion voltage of the voltage (V) to the unselected scan electrode (Y _m ). 2. The method for driving a liquid crystal display device according to claim 1, wherein the negative voltage application mode period for applying the voltage of 1 is repeated for the same period. 3. When selectively driving a plurality of liquid crystal cells corresponding to each of the scan electrodes (Y _m ), each of a plurality of display data of the liquid crystal cells corresponding to one of the scan electrodes (Y _m ). but displays each constituted the liquid crystal cell with a the respective display data selected immediately before (one with the scan electrode of the scan electrode (Y _m) (Y _m) data electrodes intersecting the (X _n) From the number of cells changing from the data), the scan electrode (Y
Each of the plurality of display data of the liquid crystal cell corresponding to one of _m) is, one with the scan electrode (Y _m) and the data electrodes intersecting the display data selected immediately before (the scan electrodes (Y _m) ( X _n ), the number of unchanged cells is subtracted from the respective display data of the liquid crystal cells), and the polarity inversion is executed only when the subtraction result is positive. Item 3. A method for driving a liquid crystal display device according to item 1 or 2. 4. A liquid crystal display panel (3) comprising liquid crystal enclosed between a plurality of intersecting data electrodes (X _n ) and scan electrodes (Y _m ) to form a plurality of liquid crystal cells in a matrix. A data driver (1) for selecting and applying a selected and non-selected pulse voltage to the data electrode (X _n ).
And a scan driver (2) for selectively applying a selected and non-selected pulse voltage to the scan electrode (Y _m ).
And a driver for driving the liquid crystal display device having a power supply circuit (4) for supplying the selection voltage and the non-selection voltage to the drivers (1) and (2), the scan electrode (Y _m ). each of the plurality of display data of the liquid crystal cell corresponding to the one of one and a data electrode (X _n intersecting with the scan electrodes (Y _m) of the display data selected immediately before (the scan electrodes (Y _m) from the number of cells varies from each of the display data) of the liquid crystal cell constituted with a with each), each of the plurality of display data of the liquid crystal cell corresponding to one of the scan electrode (Y _m) is, immediately before display data selected in (the scan electrodes (Y _m) one with the scan electrode (Y _m) and data electrodes intersecting each said liquid crystal cell each formed with a a (X _n) of An arithmetic circuit (5) for subtracting the number of unchanged cells from the display data) and a polarity inversion signal output circuit (6) for outputting an inversion signal only when the output of the arithmetic circuit (5) is positive. A liquid crystal display device having a driving device characterized by. 5. A liquid crystal cell arranged in a matrix,
With respect to the voltage applied to the data electrodes selected (X _n), by applying a voltage (V) to the scan electrodes (Y _m) to be selected, the voltage on the data electrodes are not selected (X _n) of (V) Means for determining a positive voltage application mode period in which a voltage of 2 / a times is applied and a voltage of 1 / a times the voltage (V) is applied to the unselected scan electrode (Y _m ) and a selected data electrode the voltage applied to the (X _n) as a reference, by applying a reversal voltage of the scan electrodes selected (Y _m) to a voltage (V), the inverted voltage of the data electrodes are not selected (X _n) to the voltage (V) the 2 / a times the voltage is applied, the means for determining a negative voltage application mode period for applying the 1 / a times the voltage of the inverting voltage of the voltage to the scan electrodes that are not selected (Y _m) (V), wherein The positive voltage application mode period and the negative voltage application mode period are the same. The liquid crystal display device having a drive unit and having a means for time increments of application.