JP2007156336A - Liquid crystal display device and driving method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device in which sounding is reduced compared with a conventional device by logically controlling the frequency of a counter electrode without causing mechanical restriction. <P>SOLUTION: The liquid crystal display device is provided with pixels each of which has a pixel electrode 9 and a counter electrode 8 and is arranged in each of intersections between a plurality of data signal lines SL and a plurality of scanning signal lines GL which intersect with each other and the liquid crystal display device is constituted so that the plurality of data signal lines SL are divided in each a group of data signal lines RSL, GSL, BSL which are continuously arranged and the data signal lines constituting a group of data signal lines RSL, GSL, BSL are successively selected within one horizontal scanning period. In the liquid crystal display device, the polarity of the counter electrode 8 and that of the pixel electrode 9 are inverted synchronously with the timing of selection/non-selection of the data signal lines SL. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device and a driving method thereof, and more particularly to a liquid crystal display device using a driving method that outputs a source signal in a time-division manner within a 1H period and a driving method thereof.

  Conventionally, one-line inversion driving is used as a driving method of a liquid crystal display device. This one-line inversion driving is a driving method in which the polarity of the counter electrode is inverted every 1H as shown in FIG. In the figure, HSYNC indicates a horizontal synchronization signal. Further, the counter electrode is driven by reversing the polarity with the input of the horizontal synchronizing signal as a trigger.

  In this driving method, the counter electrode inversion period is 2H as shown in FIG. Charges are accumulated in the counter electrode, and when this charge repeats + and-, the Coulomb force acts on the plastic plate (display plate, acrylic plate) that covers the surface of the liquid crystal panel, causing the plastic plate to vibrate and generate sound. A ringing occurs. If this sounding frequency is a frequency that can be heard by the human ear, abnormal sound may be a problem.

On the other hand, in Patent Documents 1 and 2, the noise is prevented by controlling the frequency of the counter electrode using a piezoelectric transformer inverter. Patent Document 3 discloses a technique for reducing the charge accumulated in the counter electrode by 0.5 nC by devising a mechanical system for the amount of charge accumulated in the counter electrode.
JP 10-66353 A (published March 6, 1998) JP 2000-295858 A (released on October 20, 2000) JP 2000-98381 A (published April 7, 2000) JP 2003-179988 A (published June 27, 2003)

  However, in Patent Documents 1 and 2 described above, it is necessary to use a piezoelectric transformer inverter, and it is desired to control the frequency logically. Moreover, in patent document 3, there exists a problem of accompanying a mechanical limitation.

  The present invention has been made in view of the above-mentioned problems, and its purpose is to control the frequency of the counter electrode logically without accompanying mechanical limitations, thereby reducing the sounding frequency from the conventional level. Another object of the present invention is to provide a liquid crystal display device and a driving method thereof.

  In order to solve the above problems, a driving method of a liquid crystal display device of the present invention includes a pixel having a pixel electrode and a counter electrode at each intersection of a plurality of data signal lines and a plurality of scanning signal lines orthogonal to each other. The plurality of data signal lines are divided into a set of consecutive data signal lines, and the data signal lines constituting the set of data signal lines are sequentially selected within one horizontal scanning period. The liquid crystal display device driving method is characterized in that the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with the selection / non-selection timing of the data signal line.

  In addition, in order to solve the above problems, the liquid crystal display device of the present invention includes a pixel having a pixel electrode and a counter electrode at each intersection of a plurality of data signal lines and a plurality of scanning signal lines orthogonal to each other, The plurality of data signal lines are divided into a set of consecutive data signal lines, and the data signal lines constituting the set of data signal lines are sequentially selected within one horizontal scanning period. In the liquid crystal display device, the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with the selection / non-selection timing of the data signal line.

  The liquid crystal display device described above divides a plurality of data signal lines into a set of data signal lines arranged continuously, and the data signal lines constituting the set of data signal lines within one horizontal scanning period. They are selected in order.

  In this driving method, since the data signal lines are sequentially selected, the selection timing and the non-selection timing are generated in the liquid crystal display device. According to the above configuration, the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with these timings.

  Therefore, the polarity cycle of the counter electrode, which has been conventionally inverted every one horizontal scanning period, can be made smaller than that of one horizontal scanning period. Therefore, the sounding frequency can be set higher than before.

  Further, in the above configuration, since the selection / non-selection timing of the data signal line is simply used, the frequency of the counter electrode can be logically controlled without any mechanical restriction. Further, since the polarity inversion frequency of the counter electrode is higher than that of line inversion driving, it is superior in display quality such as crosstalk / flicker. Since the polarity inversion frequency of the counter electrode is smaller than that of the dot inversion driving, the current consumption can be reduced.

  In the liquid crystal display device of the present invention, the data signal lines are sequentially selected, so that one horizontal scanning period is divided into a plurality of divided periods, and the polarity of the counter electrode and the polarity of the pixel electrode are set for each divided period. Inversion is preferred.

  In the liquid crystal display device of the present invention, it is preferable that a switch for selecting / deselecting the data signal line is provided for each set of data signal lines. According to the above configuration, since the selection of the data signal line is performed by the switch, the selection / non-selection of the data signal line can be performed with a simple configuration.

  The set of data signal lines is preferably three data signal lines corresponding to the three primary colors for constituting the display color.

  The liquid crystal display device of the present invention further includes timing signal generation means for generating a timing signal for controlling selection / non-selection of the data signal, and counter electrode polarity inversion means for inverting the polarity of the counter electrode. The timing signal generating means sends the timing signal to the counter electrode polarity inversion means, while the counter electrode polarity inversion means can invert the polarity of the counter electrode based on the received timing signal. preferable.

  According to the above configuration, the timing signal generated by the timing signal generation unit and originally used for switching the data signal line is also sent to the counter electrode polarity inversion unit that has inverted the polarity of the counter electrode. The counter electrode polarity inversion means reverses the polarity of the counter electrode using this timing signal. Therefore, the polarity of the counter electrode can be reversed only by using the originally used timing signal.

  In the liquid crystal display device of the present invention, it is preferable that adjacent scanning signal lines have different polarities of counter electrodes and pixel electrodes of pixels connected to these scanning signal lines.

  According to the above configuration, in the adjacent scanning signal lines, the polarities of the counter electrodes of the pixels connected to these scanning signal lines and the polarities of the pixel electrodes are different. Therefore, since the polarity of the pixel electrode is different for each scanning signal line, display unevenness due to the difference in polarity is made uniform over the entire screen, and the display quality is improved.

  In the liquid crystal display device, it is preferable that the polarity of the counter electrode and the polarity of the pixel electrode are different every vertical scanning period.

  As described above, the liquid crystal display device and the driving method thereof according to the present invention include a pixel having a pixel electrode and a counter electrode at each intersection of a plurality of data signal lines and a plurality of scanning signal lines orthogonal to each other. A plurality of data signal lines are divided for each set of data signal lines arranged continuously, and the data signal lines constituting the set of data signal lines are sequentially selected within one horizontal scanning period. In the driving method of the liquid crystal display device, the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with the selection / non-selection timing of the data signal line. Therefore, by controlling the frequency of the counter electrode in a logical manner without any mechanical restrictions, it is possible to reduce the sound generation compared to the conventional case.

[Configuration of liquid crystal display device]
An embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 2, the liquid crystal display device of the present embodiment includes a liquid crystal panel 1, a data signal line driving circuit 2, and a scanning signal line driving circuit 3. The liquid crystal panel 1 is composed of two transparent substrates, a matrix substrate 4 and a counter substrate 5 which are arranged to face each other at a distance, and a liquid crystal is filled between the substrates 4 and 5. The matrix substrate 4 is provided with pixel electrodes (see FIG. 3), while the counter substrate 5 is provided with a counter electrode 8.

  As shown in FIG. 3, the matrix substrate 4 includes a plurality of scanning signal lines (gate bus lines) GL and a plurality of data signal lines (source bus lines) RSL / GSL / BSL (SL) orthogonal to each other. Have. The driving method of the liquid crystal display device according to the present embodiment is a driving method in which a source signal is divided into three and output in one horizontal scanning period. This liquid crystal display device is driven by a group of a plurality of data signal lines (in this embodiment, three data signal lines RSL, GSL, and BSL) that are output to a common output circuit (described later). ). Therefore, the data signal line SL is divided for each set of data signal lines RSL, GSL, and BSL arranged continuously.

  Further, at the intersection of the scanning signal line GL and the data signal line RSL, the intersection of the scanning signal line GL and the data signal line GSL, and the intersection of the scanning signal line GL and the data signal line BSL, respectively, R pixels PIX, G pixel PIX or B pixel PIX is provided, and these pixels PIX are two-dimensionally arranged to form a pixel portion 19.

  More specifically, “R pixel PIX” is provided at the intersection of the scanning signal line GL and the data signal line RSL, and “G pixel PIX” is provided at the intersection of the scanning signal line GL and the data signal line GSL. ”And“ B pixel PIX ”is provided at the intersection of the scanning signal line GL and the data signal line BSL. Note that R, G, and B represent the three primary colors for constituting the display color.

  Each of the R pixel PIX, the G pixel PIX, and the B pixel PIX includes a TFT 6, a liquid crystal capacitor 7, a counter electrode 8, and a pixel electrode 9, as shown in FIG. The TFT 6 serves as a switching element for the R pixel PIX, the G pixel PIX, and the B pixel PIX. The source of the TFT 6 is connected to one of the data signal lines RSL, GSL, and BSL, while the drain of the TFT 6 is connected to the liquid crystal capacitor 7. That is, the liquid crystal capacitor 7 is connected to any of the data signal lines RSL, GSL, and BSL via the TFT 6. The gate of the TFT 6 is connected to the scanning signal line GL. Opening / closing of the gate of the TFT 6 is selected by a scanning signal supplied from the scanning signal line GL, and connection / disconnection of the data signal line RSL / GSL / BSL and the liquid crystal capacitor 7 can be switched. The counter electrode 8 provided on the counter substrate 5 facing the pixel electrode 9 on the TFT 6 side in the liquid crystal capacitor 7 is a common electrode.

  As shown in FIG. 3, an analog switch (switch) SW is provided on the upstream side of the set of data signal lines RSL / GSL / BSL in the liquid crystal display device. That is, one switch SW is assigned to the three pixels PIX of the R pixel PIX, the G pixel PIX, and the B pixel PIX. Furthermore, in other words, one switch SW is assigned to a set of data signal lines RSL, GSL, and BSL arranged continuously.

  The switch SW selects a data signal line in the order of RSL, GSL, and BSL in accordance with a timing signal from a timing signal generation unit 14 (see FIG. 2), which will be described later, and a data signal line and a data signal line driving circuit. The connection with 2 is switched sequentially. That is, the switch SW is a data signal line switch for switching the supply of data from the output circuit 10 of the data signal line driving circuit 2 to the data signal line SL in the order of RSL / GSL / BSL. Here, the supply of data from the output circuit 10 to the data signal line SL is switched in the order of RSL, GSL, and BSL. However, this is merely an example, and the order of RSL, GSL, and BSL is not limited. Absent.

As shown in FIG. 2, the data signal line driving circuit 2 includes an output circuit 10, a timing signal generation unit (timing signal generation unit) 14, and a counter electrode polarity inversion unit (counter electrode polarity inversion unit) 15. is doing. As shown in FIG. 2, the output circuit 10 has a plurality of (for example, 120) original data signal lines, and has a role of supplying video data to the liquid crystal panel 1.
As can be seen from FIG. 3, the number of the original data signal lines is 1/3 of the total number of the data signal lines RSL, GSL, and BSL. The timing signal generation unit 14 has a role of sending a pixel selection signal (timing signal) to the switch SW and sequentially switching the switch SW between R, G, and B. It should be noted that the switching of the switch SW is not limited to the order of R, G, and B, but may be in any order such as G, R, and B.

  In particular, in the present embodiment, the timing signal generator 14 supplies the timing signal to the output circuit 10 and the counter electrode polarity inverter 15. The counter electrode polarity inversion unit 15 receives the timing signal and inverts the polarity of the counter electrode 8 in synchronization with (a part or all of) the switching timing of the switch SW.

  By the way, in order to write a voltage to the liquid crystal, it is necessary to apply a voltage (charge the liquid crystal) from both sides of the liquid crystal. That is, two signal lines are required, and the polarity of the signal flowing through both of these signal lines must be reversed. Therefore, as shown in FIG. 4, each pixel PIX is provided with a counter electrode signal line and an RGB signal line, and outputs (RGB signals) from the output circuit 10 in accordance with the inversion of the polarity of the counter electrode 8. ) (The polarity of the pixel electrode 9) is also inverted based on the received timing signal.

[Operation of liquid crystal display device]
Next, the operation of the timing signal generator 14 will be described with reference to FIG.

  Here, the operation of the timing signal generation unit 14 in one horizontal scanning period from the input time (t0) of a certain horizontal synchronization signal to the input time (t7) of the next horizontal synchronization signal will be described. The timing signal generator 14 repeats the same operation every horizontal scanning period.

  The timing signal generation unit 14 uses the input of the horizontal synchronization signal as a trigger, and at t1, when a predetermined time has elapsed from the input of the horizontal synchronization signal, RSW_O becomes “high level (H); selection of data signal line”, and t2 (> At t1), an R pixel selection signal (timing signal) is supplied to the switch SW so that RSW_O becomes “low level (L); non-selection of data signal line”. Thereby, from t1 to t2, the data signal line RSL is selected by the switch SW, the video data from the output circuit 10 is input to the R pixel PIX, and the liquid crystal is charged to the R pixel PIX.

  Thereafter, the timing signal generation unit 14 supplies a G pixel selection signal (timing signal) to the switch SW so that GSW_O becomes “H” at t3 and GSW_O becomes “L” at t4 (> t3). Thereby, at t3 to t4, the data signal line GSL is selected by the switch SW, the video data from the output circuit 10 is supplied to the G pixel PIX, and the liquid crystal is charged to the G pixel PIX.

  Further, the timing signal generation unit 14 supplies a B pixel selection signal (timing signal) to the switch SW so that BSW_O becomes “H” at t5 and BSW_O becomes “L” at t6 (> t5). Thus, at t5 to t6, the data signal line BSL is selected by the switch SW, the data from the output circuit 10 is supplied to the B pixel PIX, and the liquid crystal is charged to the B pixel PIX.

  By such a timing signal from the timing signal generator 14, the horizontal scanning period is A period (t0 to t1), B period (t1 to t2), C period (t2 to t3), D period (t3 to t4). ), E period (t4 to t5), F period (t5 to t6), and G period (t6 to t7). Further, the timing signal generation unit 14 sends the above timing signal not only to the switch SW but also to the counter electrode polarity inversion unit 15 and the output circuit 10. Note that t1, t3, and t5 are data signal line selection timings, and t2, t4, and t6 are data signal line non-selection timings.

  Next, the operation of the counter electrode polarity reversing unit 15 will be described with reference to FIG.

  In FIG. 1, HSYNC indicates a horizontal synchronization signal. In FIG. 5, the hatched portions (RSW, GSW, BSW) in SW are the period in which RSW_O is “H”, the period in which GSW_O is “H”, and the period in which BSW_O is “H”. Is shown.

  Here, in particular, the counter electrode polarity reversing unit 15 of the present embodiment has a role of sending a polarity reversal signal to the counter electrode 8 and inverting the polarity of the counter electrode 8. The polarity inversion signal is generated based on the timing signal received from the timing signal generation unit 14. Here, as an example, in synchronization with the timing t1 (data signal line selection timing), t3 timing (data signal line selection timing), and t5 timing (data signal line selection timing). A polarity inversion signal for inverting the polarity of the counter electrode 8 is generated and supplied to the counter electrode 8, and the polarity of the counter electrode 8 is inverted based on the polarity inversion signal. Thereby, as shown in FIG. 1, the sounding period (inversion period of the counter electrode) can be reduced to about 1/3 of the conventional one. That is, the sounding frequency can be increased by about three times the conventional frequency. Specifically, the frequency can be changed from the frequency 11.7 KHz which is an audible range to 35.2 KHz.

  Therefore, the inversion period of the counter electrode can be set to a period exceeding the human audible range. In addition, the driving according to the present embodiment is superior in display quality such as crosstalk / flicker because the polarity inversion frequency of the counter electrode is higher than that of so-called line inversion driving. In the driving of the present embodiment, since the polarity inversion frequency of the counter electrode is smaller than that of so-called dot inversion driving, power consumption can be reduced.

  In addition, as described above, in order to write a voltage to the liquid crystal, it is necessary to apply a voltage from both sides of the liquid crystal. Therefore, in this embodiment, for example, the source when the display screen is “white display” As shown in FIG. 1, the output (all white) level is switched between “+” and “−” at t1, t3, and t5 (see FIG. 6A). That is, the polarity of the pixel electrode 9 is switched at t1, t3, and t5. That is, the polarity of the video data (the polarity of the pixel electrode 9) is reversed in accordance with the reversal of the polarity of the counter electrode 8.

  Further, for example, the source (all black) level when the display screen is “black display” is similarly switched between “+” and “−” at t1, t3, and t5 as shown in FIG. (See FIG. 6B).

  Furthermore, as shown in FIG. 1, the pixels PIX connected to the adjacent scanning signal lines (GLn and GLn + 1) have different polarities of the counter electrode 8 and the pixel electrode 9 from each other. It is preferable. Here, the polarity of the counter electrode 8 in the horizontal scanning period (t0 to t7) and the polarity of the counter electrode 8 in the next horizontal scanning period (t7 to t14) are reversed. That is, it is preferable to change the polarity of the counter electrode 8 and the polarity of the video data (the polarity of the pixel electrode 9) for each scanning signal line (one gate line).

  However, the present invention is not limited to this, and as shown in FIG. 7, the polarity of the counter electrode 8 and the polarity of the pixel electrode 9 may be different for every two gate lines. In this case, as shown in the figure, the polarity of the counter electrode 8 and the polarity of the pixel electrode 9 in the scanning signal lines GLn and GLn + 1 are equal to each other, and in the scanning signal lines GLn + 2 and GLn + 3 (not shown), The polarity of 8 and the polarity of the pixel electrode 9 are reversed.

  Also, as shown in FIG. 8, it is preferable that the polarity of the counter electrode 8 and the polarity of the video data are different at the next 1V. That is, it is preferable that the polarity of the counter electrode 8 and the polarity of the video data are different every 1V.

  In the above description, the counter electrode polarity reversing unit 15 reverses the polarity of the counter electrode 8 at t1, t3, and t5 (t8, t10, and t12) as shown in FIG. However, the present invention is not limited to this, and the polarity of the counter electrode 8 may be reversed at t1, t3 (t8, t10) as shown in FIG. 9, or t1, t5 (t8, t12 as shown in FIG. 10). ), The polarity of the counter electrode 8 may be reversed. 11A and 11B show the pixel charge polarity in the driving method as shown in FIG. In these cases, the sounding period (inversion period of the counter electrode 8) can be halved compared to the conventional one. Similarly, the inversion period of the counter electrode 8 can be set to a period exceeding the human audible range. Although not shown, the polarity of the counter electrode 8 may be reversed at t3 and t5.

  Further, as described above, the horizontal scanning period can be divided into seven periods (A period to G period) by the operation of the timing signal generation unit 14.

Since the polarity of the counter electrode 8 is “H” or “L” in all periods, the polarity pattern of the counter electrode 8 is
"H, H, H, H, H, H, H"
“H, H, H, H, H, H, L”
“H, H, H, H, H, L, L”
...
“H, H, L, L, L, L, L”
“H, L, L, L, L, L, L”
"L, L, L, L, L, L, L"
There are 128 patterns. However, when all the polarities of the counter electrode 8 are “H” or all are “L”, they are the same as the line inversion driving, and these are excluded from the present embodiment. 2 = 126.

  In the above description, the polarity inversion of the counter electrode is performed at t1, t3, and t5. That is, the polarity of the counter electrode is reversed at the timing when RSW_O, GSW_O, or BSW_O becomes “H”. However, the present invention is not limited to this, and the polarity of the counter electrode 8 may be reversed at the timing when RSW_O, GSW_O, or BSW_O becomes “L” (data signal line non-selection timing). That is, “in one horizontal scanning period, the polarity of the counter electrode 8 and the polarity of the pixel electrode 9 are inverted in synchronization with (at least one of) the switch SW ON / OFF switching timing used for SSD driving. "To do" is the technical idea of the present invention. Thereby, the inversion period of a counter electrode can be made smaller than before. Therefore, the counter frequency can be easily brought to a frequency higher than the audible range.

  In this embodiment, the case where one horizontal scanning period (horizontal period) is divided into three parts has been described, but it may be divided into six parts or nine parts.

  Further, the driving method of the liquid crystal display device of the present embodiment is different in the counter electrode polarity inversion period from that in the dot inversion driving. In general dot inversion driving, the counter electrode becomes DC and there is no inversion cycle. In the dot inversion drive, the polarity of the RGB signal lines is inverted every 1 DOTCLK instead. Thereby, f of the liquid crystal charge / discharge current (I = fclV) becomes 1 DOTCLK, and the consumption current becomes higher than that of the present embodiment. In the present embodiment, the inversion periods of the RGB signal lines and the counter electrode signal lines are about 1/2 times and 1/3 times, which is shorter than general dot inversion driving.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.

  The liquid crystal display device and the driving method thereof of the present invention can be particularly suitably used for a mobile phone or a PDA.

4 is a timing chart illustrating the polarity of a counter electrode according to an embodiment of the present invention. 1 is a block diagram illustrating a schematic configuration of a liquid crystal display device according to an embodiment of the present invention. 1, showing an embodiment of the present invention, is an explanatory diagram showing a configuration on a matrix substrate. FIG. 1 is an explanatory diagram illustrating an embodiment of the present invention and enlarging one pixel. 4 is a timing chart illustrating an operation of a switch in an SSD driving method according to an embodiment of the present invention. FIG. 2 shows an embodiment of the present invention, and FIGS. 4A and 4B are tables showing pixel charge polarities in the timing chart shown in FIG. FIG. 5 is a timing chart illustrating an embodiment of the present invention, in which the polarity of the counter electrode is reversed every 2H. FIG. 5 is a timing chart illustrating an embodiment of the present invention, in which the polarity of the counter electrode is reversed every 1V. FIG. 4 is a timing chart illustrating the embodiment of the present invention, in which the polarity inversion period of the counter electrode can be halved. FIG. 10 illustrates an embodiment of the present invention and is a timing chart illustrating an example different from FIG. 9. FIG. 4 shows an embodiment of the present invention, and (a) and (b) are tables showing pixel charge polarities in the timing chart shown in FIG. It is a timing chart which shows a prior art and shows the polarity of a counter electrode.

Explanation of symbols

8 Counter electrode 9 Pixel electrode 14 Timing signal generator (timing signal generator)
15 Counter electrode polarity inversion part (Counter electrode polarity inversion means)
GL scanning signal line SL data signal line RSL data signal line GSL data signal line BSL data signal line SW switch PIX pixel A period (division period)
Period B (split period)
C period (division period)
D period (split period)
E period (division period)
F period (split period)
G period (split period)
R Display color G Display color B Display color 1H Horizontal scanning period 1V Vertical scanning period

Claims (8)

A pixel having a pixel electrode and a counter electrode at each intersection of a plurality of data signal lines and a plurality of scanning signal lines orthogonal to each other,
The plurality of data signal lines are divided into a set of consecutive data signal lines, and the data signal lines constituting the set of data signal lines are sequentially selected within one horizontal scanning period. In the driving method of the liquid crystal display device
A driving method of a liquid crystal display device, wherein the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with the selection / non-selection timing of the data signal line. A pixel having a pixel electrode and a counter electrode at each intersection of a plurality of data signal lines and a plurality of scanning signal lines orthogonal to each other,
The plurality of data signal lines are divided into a set of consecutive data signal lines, and the data signal lines constituting the set of data signal lines are sequentially selected within one horizontal scanning period. In the liquid crystal display device
A liquid crystal display device, wherein the polarity of the counter electrode and the polarity of the pixel electrode are inverted in synchronization with the selection / non-selection timing of the data signal line.   By selecting the data signal lines in order, one horizontal scanning period is divided into a plurality of divided periods, and the polarity of the counter electrode and the polarity of the pixel electrode are inverted in each divided period. .   3. The liquid crystal display device according to claim 1, further comprising a switch for selecting / deselecting the data signal line for each set of data signal lines.   4. The liquid crystal display according to claim 1, wherein the set of data signal lines is three data signal lines corresponding to each of the three primary colors for constituting a display color. apparatus. And a timing signal generating means for generating a timing signal for controlling the selection / non-selection of the data signal, and a counter electrode polarity inverting means for inverting the polarity of the counter electrode,
The timing signal generating means sends the timing signal to the counter electrode polarity inverting means, and the counter electrode polarity inverting means inverts the polarity of the counter electrode based on the received timing signal. The liquid crystal display device according to claim 1.   6. The liquid crystal according to claim 1, wherein the adjacent scanning signal lines have different polarities of the counter electrodes of the pixels connected to these scanning signal lines and the polarities of the pixel electrodes. 7. Display device.   7. The liquid crystal display device according to claim 1, wherein the polarity of the counter electrode and the polarity of the pixel electrode are different every vertical scanning period.

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