JPH0573003A - Method for driving liquid crystal display device - Google Patents

Abstract

PURPOSE:To obtain a method for driving a liquid crystal display device(LCD) by which the quality of a displayed picture is improved without causing display like ghost caused in an area which is not an original display area by crosstalk whatever display data is. CONSTITUTION:In a specified period in one cycle selective driving period, all the liquid crystal elements in a liquid crystal panel 1 are forcibly made in a non-selective state, whether the liquid crystal element is selected or not. Thus, AC (pulse) voltage being the almost effective voltage of ground voltage is always impressed on the liquid crystal element and a DC component is not left. By AC-driving the liquid crystal element, the display like ghost by the crosstalk is prevented and there is no irregularity in display content. As for a concrete method, the same voltage at a level where the liquid crystal element does not act is impressed on the terminal of the liquid crystal element for a time shorter than the half of the selective driving time according to a display off control signal DSPOFF from an LCD control circuit 3. Or an alternating pulse control signal M0 is shifted for a time within the half of the selective driving time TS.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of driving a liquid crystal display device, and more particularly, to a method of driving a liquid crystal display device (LCD) for preventing ghost display due to occurrence of crosstalk and improving display quality. Regarding

[0002]

2. Description of the Related Art Various driving methods have been proposed as a driving method for a liquid crystal display device, but they are accompanied by driving through a liquid crystal element which is a capacitance load and a transparent electrode having a finite resistance value. The applied voltage waveform becomes dull. In particular,
In the case of a large-sized LCD, the overall capacitance increases, the wiring resistance of the transparent electrode increases, and the driving frequency increases, so that the dullness of the waveform cannot be ignored and the display image quality deteriorates. A line inversion drive method is known as a measure for improving the image quality of a large-capacity matrix LCD. This line inversion drive method changes the polarity every time a certain number of lines are driven even within one frame, and suppresses the effective voltage difference of the pixel that occurs depending on the ON / OFF display pattern. To reduce the difference in transmittance,
This is a method for uniformly improving the image quality. Even in such a line inversion driving method, crosstalk still occurs according to the display data pattern. As a method of improving the line inversion driving method for improving crosstalk, in the driving of a simple matrix type STN-LCD, all the scanning electrodes are selectively written with the same polarity in the first frame, and alternated for each scanning electrode in the second frame. A method has been proposed in which selective writing is performed by changing the polarity (for example, "ST
Countermeasures against N-LCD Crosstalk ", Murakami, et al., 1990 Spring National Convention of the Institute of Electronics, Information and Communication Engineers, C-512).
However, this improved line inversion driving method is effective to some extent in the simple matrix type STN-LCD, but it is a nonlinear element MIM (Metal-insulator-metal).
It cannot be applied to active matrix LCDs that use elements or back-to-back diodes. There is a problem in that flicker also occurs in this improved line inversion drive system.

For an active matrix type LCD,
A method in which the signal is inverted every 1 or 2 timing signals is also known (for example, "Liquid Crystal Device Handbook", edited by Japan Society for the Promotion of Science, 142 committee, published by Nikkan Kogyo Shimbun, pp. 421-427). ..

[0004]

However, even in such a driving method, there is still a difference in the effective voltage between the pixel in which the DC component remains in the pixel applied voltage and the pixel in which the DC component does not remain depending on the display data pattern. There is a problem that a ghost is generated due to crosstalk. Therefore,
SUMMARY OF THE INVENTION It is an object of the present invention to provide an LCD driving method for improving display image quality on an LCD without generating a ghost due to crosstalk regardless of a display data pattern.

[0005]

In order to solve the above problems, according to the present invention, an AC voltage is applied to a liquid crystal panel in which a plurality of liquid crystal elements are arranged in a matrix in the column and segment directions. In a liquid crystal display device driving method in which the liquid crystal display device is applied and selectively driven, the total selection drive timing is a predetermined time of a time for selectively driving one liquid crystal element, regardless of whether it is selected or not selected. There is provided a liquid crystal display device driving method characterized by forcibly setting a liquid crystal element to a non-selected state. Specifically, the liquid crystal element has a voltage level that alternates within a time period for selectively driving one liquid crystal element so that the same voltage is applied to both ends of the liquid crystal element when the liquid crystal element is in a non-selected state. A pulse voltage is applied to the liquid crystal element from the column and segment directions. In addition, specifically, an AC pulse control signal for applying an AC voltage to the liquid crystal panel having a frequency that defines the time for selectively driving one liquid crystal element is set within half of the selective drive time from the normal timing. Move for a predetermined time. More preferably, the liquid crystal element is brought into a non-selected state for a time corresponding to a shift of the AC pulse control signal for a predetermined time. Further, according to the present invention, as the display data for driving one liquid crystal element, the data to be displayed on the liquid crystal element and the data having the inverse logic of the display data are consecutively displayed, and the frequency for selectively driving one liquid crystal element is set. A method of driving a liquid crystal display device is provided, in which a liquid crystal element is driven at a frequency twice as high as a voltage applied at a frequency twice.

[0006]

[Operation] By displaying the liquid crystal element by making the liquid crystal panel in the non-selected state for a predetermined time out of the time corresponding to the time for selectively driving the liquid crystal element, regardless of whether the liquid crystal element is selected or not selected. Regardless of the data, AC voltage is always applied and no DC component remains. Therefore, since the voltage applied to the pixels is almost at the ground level, the effective voltage difference between the pixels is small, crosstalk does not occur, and it is possible to avoid the ghost display phenomenon and the unevenness of the display screen due to the crosstalk.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a block diagram of an LCD driving device applied to a liquid crystal display device driving method of the present invention. This LCD
The drive device is configured by connecting a liquid crystal panel 1, an LCD control circuit 3, column drivers 5-6, and segment drivers 8-9 as shown in the figure. The liquid crystal panel 1 has 640
The x480 MIM type liquid crystal elements are arranged in a matrix. Each of the column drivers 5-6 selectively drives 160 columns, and the three column drivers 5-6 selectively drive 480 columns. Each of the segment drivers 8 to 9 also selectively drives 160 segments, and the four segment drivers 8 to 9 selectively drive 640 segments. The liquid crystal elements arranged in a matrix are selectively driven by the selection of these columns and the selection of the segments. The LCD control circuit 3 selectively drives the liquid crystal elements through the column drivers 5-6 and the segment drivers 8-9.

FIG. 2 shows the internal circuit configuration of the column driver 5. The column driver 5 includes a data strobe DST,
A control circuit 5 for controlling the circuits in the column driver 5 by inputting the system clock SCK, the mode signal MODE, etc.
1, bit latch selection circuit 52, data latch circuit 5
3, bit data multiplexer 54, data latch and bidirectional data shift circuit 55, level shift circuit 5
6, a logic circuit 57 and a driver circuit 58. The driver circuit 58 outputs 160 liquid crystal column drive voltages. In order to control this drive voltage output, the LCD control circuit 3 sends the display off control signal DS to the driver circuit 58.
POFF is applied. The column driver 6 also has the same circuit configuration as the column driver 5.

FIG. 3 shows a partial circuit configuration of the driver circuit 58. The display off control signal DSPOFF is supplied to the inverter 58.
1, the NOR gate 582, the NOR gate 583, and the inverter 584 are used to activate (turn on) the MOS transistor that outputs the voltage V _L2 . This voltage V _L2 corresponds to a low potential for turning off the driving of _the liquid crystal element, as will be described later. An alternating pulse control signal M ₀ is applied to the NOR gate 582. Other voltages V _L1 , V _L3 for driving the LCD device via other MOS transistors,
_VL4 is output.

[0010] level V _L1 ~V _L5 of the liquid crystal element drive voltage as described above in FIG. 4, V _EE, the level of the voltage V _L1 COM~V _L4 COM applied to the liquid crystal pixel from the column drivers, the liquid crystal pixel from the segment driver Voltage applied to V _L1
SEG~V _L4 COM level, alternating pulse control signal M
Voltage level of logic state “0” or “1” of o, difference between column driver voltage and segment driver voltage in selective drive state SEL: white WH corresponding to COM-SEG
Display state of T or black BLK, non-selected drive state DES
The difference between the column driver voltage and the segment driver voltage in EL: The display state of white WHT or black BLK according to COM-SEG is shown. FIG. 5 shows a pixel applied voltage waveform. 1H indicates one scanning time. FIG. 5 shows all cases of the AC pulse control signal Mo and the pixel applied voltage in the selective drive state SEL and the non-selected state DESEL. WHT and BLK represent data to be written in the selected pixel. The voltage shown in parentheses is the voltage according to the exemplary voltage shown in FIG. The relationship between the voltage application state and the display state of the liquid crystal element shown in FIGS. 4 and 5 is the same as that of the conventional line inversion driving method. In addition,
The above voltage values are examples.

When the driving state is specifically shown using the exemplary voltage shown in FIG. 4, when the white display WHT is displayed on the panel selection pixel SEL, if Mo is "1", the potential output from the column driver is V. _L1 COM (+ 5V), the potential output from the segment driver is V _L2 SEG (−23V), and the pixel applied voltage (voltage between A and C in FIG. 5) is the potential difference V _L1 between them.
It is driven by COM-V _L2 SEG (+ 28V). At this time, the non-selected pixel DESEL is driven with the output potential from the column driver being V _L4 COM (−20.5 V) and the pixel applied voltage being V _L4 COM−V _L2 SEG (+2.5 V). If Mo is “0”, the potential output from the column driver is V _L2 COM (−23 V), the potential output from the segment driver is V _L1 SEG (+5 V), and the pixel applied voltage is V _L2 COM−V _L1. It is driven by SEG (-28V). At this time, the non-selected pixel DESEL is driven by the column driver with an output potential of V _L3 COM (+2.5 V) and a pixel applied voltage of V _L3 COM−V _L1 SEG (−2.5 V). When displaying the black display BLK, the table is displayed in the same manner as above.
Driven according to 1. Table 1 shows an alternating pulse control signal Mo based on the liquid crystal element drive voltage shown in FIG. 4, a selective drive state SEL, and a non-selective drive state DESEL, Dat.
6 is a table showing a relationship between a and a pixel applied voltage.

[Table 1]

Before describing an embodiment of a liquid crystal display device (LCD) driving method of the present invention, referring to FIG.
The D drive method and its problem will be described. In the conventional LCD driving method, the display-off control signal DSPOFF generated in the LCD control circuit 3 does not exist, but it is shown in FIG. 6A for comparison with the LCD driving method of the present invention. However, the display off control signal DSPOFF does not change at the "high (H)" level. Therefore, the voltage V due to the display-off control signal DSPOFF, which will be described later,
_There is no pulse-like change in _L2 . 6B and 6C, the voltage applied between the nth column driver and the nth segment driver: COM _n -SEG _n , the nth column driver and the (n + 1) th segment driver, respectively. The voltage waveform between COM _{n and} SEG _{n + 1} is shown in FIG.
As shown in (B), a DC component may remain with respect to the ground voltage (ground level) GND. This DC component increases the effective voltage difference of the pixel due to crosstalk as compared with a pixel having a small DC component, causes ghost display due to a ghost phenomenon described later, and deteriorates the display image quality.

In the LCD driving method according to the first embodiment of the present invention, as shown in FIG. 7, a pulse-shaped display-off control signal alternating with a time T _S for selectively driving one liquid crystal element as one cycle (1H). outputs DSPOFF from the LCD control circuit 3 (FIG. 7 (B)), the voltage V _L2 of the liquid crystal element de-energizing the voltage level from the driver circuit 58 in the column driver 5 selectively drive time T _S, T _S in this embodiment Output for a predetermined time less than half of 64 μs, for example, 10 μs. The selective drive time T _S is equal to the AC pulse control signal M ₀ (see FIG.
(A)). The display off control signal DSPOFF is also applied to the segment driver 8,
A circuit (not shown) in the segment driver 8 corresponding to the driver circuit 58 outputs the voltage V _L2 for a predetermined time within half the time T _S. As a result, regardless of whether the liquid crystal element is selected or not, the terminal voltage of the liquid crystal element is forcibly lowered for a predetermined time period less than half the driving time T _{S by} the voltage level V.
_An equal voltage is obtained at _L2 , and the difference between the effective voltages in FIGS. 7C, 7D, and 7E is small. Display off control signal DSP
Since OFF is applied from the LCD control circuit 3 to all the column drivers 5-6 and the segment drivers 8-9 at the same time, all the liquid crystal elements, that is, all the liquid crystal elements in the liquid crystal panel 1 have time T _S. The voltage level becomes a low voltage level for a predetermined time less than half of that, and as shown in FIGS. 7C to 7E, an AC voltage is constantly applied to the LCD device.
The DC component generated depending on the display data pattern as shown in (B) does not remain. That is, according to the LCD driving method of the present invention, the liquid crystal element is AC driven without depending on the display data pattern.

FIG. 8 shows a reference display example for evaluating the display image quality on the liquid crystal panel based on the LCD driving method of FIGS. 6 and 7 described above. The display example of this standard is divided into the upper part and the lower part of the liquid crystal panel, and the upper part of 200H has a white background (WHT) as a background (surrounding background) and has a vertical direction at equal intervals (0.4 mm) in the horizontal direction. Multiple black lines (BLK) with different lengths are displayed on the lower part, and the lower 200H is black (BLK), and white lines (WHT) are displayed in the same interval and length as the upper black line. .. As for the upper 200H, 40H is a white background, 40H is a short black line in the lateral direction, 40H is a black line having an intermediate length in the lateral direction, and further 40H.
Only a black line that is long in the horizontal direction, and 40H below that is displayed as a white background. The lower part 200 is the display content opposite to the above-mentioned upper part.

FIG. 9 shows a display result by the conventional LCD driving method shown in FIG. When the display result of the upper part 200H is analyzed, firstly, it is noticeable that a thin black line is displayed with the width of the region C on the white background of the region G that should not be displayed, that is, the region C. In the display state, the right side G _R is darker than the left side G _L. This ghost-like display is displayed thinner than the original black line, but it is visible and visible with the naked eye. The vertical width of the ghost display line is 0.2 mm, which is almost half of the original vertical width of 0.4 mm of the regions A, B, and C. In the lower 200H as well, in the area F, the base of the white line of the lower F _B is darker than that of the white line of the upper F _U. Since the lower part of the area F is black (BLK), the ghost display due to the ghost phenomenon as in the upper area G cannot be detected.
The ghost phenomenon occurring in this region G is due to crosstalk. As shown in FIG. 6 (B), the conventional LC
In the D drive method, a direct current component is applied to the liquid crystal element depending on the display (segment) data, which prevents discharge from the liquid crystal element. That is, since the alternating pulse control signal M ₀ is alternating every 1H and the segment data is also changing every 1H, a DC component remains. Since the direct current components in the selected state and the non-selected state have the same polarity, the liquid crystal element as a pixel is displayed in white when it is difficult to discharge, and is displayed in black when the discharge proceeds too much. In particular, since the MIM element is a non-linear element, the imbalance of the characteristics due to the polarity cannot be avoided, and the above problem becomes remarkable. Further, in the areas A, B and C, the display image quality is also deteriorated. Originally, the data of the black line that is displayed with a uniform density in the horizontal direction is output, but the display result shows that the density of the black line is higher (darker) in the order of areas A, B, and C, and the area division is Can be seen. That is, although the black line should have a uniform density in the lateral direction, the density of the black line in the area B is higher than that of the area A, and the density of the black line in the area C is higher than the density of the black line in the area B. Is high. As for the region C, the lower C _B has a higher concentration than the upper C _U. Thus, originally _, uniform (uniform) lines with different lengths should be displayed, but from the left to the right of the LCD panel
_The black line is darker from the bottom to the top of region C,
Uniform display results cannot be obtained.

FIG. 10 shows a display result according to the first embodiment of the LCD driving method of the present invention shown in FIG. Almost no ghost display due to the ghost phenomenon illustrated in FIG. 9 occurred. As shown in FIG. 7, the display off control signal DSPOF
This is because the DC component is eliminated by F, the difference in effective voltage between the liquid crystal pixels (voltage between A and B in FIG. 18) is reduced, and the difference in liquid crystal transmittance is reduced. Further, according to the first embodiment of the LCD driving method of the present invention described with reference to FIG. 7, the areas A, B and C and the areas D, E and F as shown in FIG. 9 can be distinguished. Display unevenness did not occur, and uniform display contents were obtained throughout the screen. Thus, according to the LCD driving method of the first embodiment of the present invention, the display-off control signal DS
With a simple configuration of applying POFF, the display image quality on the liquid crystal panel can be improved.

What has been found from the first embodiment of the LCD driving method of the present invention described above is that, regardless of whether the liquid crystal element is selected or not selected for a predetermined period of one cycle of the selective driving period,
By setting the terminal voltages of all the liquid crystal elements in the liquid crystal panel 1 to "0" to bring them into a non-selected state, it is possible to improve the display image quality on the liquid crystal panel and prevent the occurrence of ghost display, flicker and the like. From this point of view, the present invention can take not only the above-described first embodiment but also various other embodiments according to the above-described principle.

FIG. 11 shows a conventional L similar to that illustrated in FIG.
It is a drive signal waveform diagram in the CD drive method. FIG. 12 is an LCD drive signal waveform diagram in the LCD drive method of the second embodiment of the present invention. The LCD driving method shown in FIG. 11 is similar to the LCD driving method shown in FIG.
The DC component remains depending on the display data. As a result, when an experiment was performed on a reference display pattern as shown in FIG. 8, the same display unevenness as shown in FIG. 9 and a ghost display due to a ghost phenomenon due to crosstalk occurred outside the display target area. In the LCD driving method of the present invention shown in FIG. 12, the alternating pulse control signal M ₀ shown in FIG. 11A is shifted by the time t _M as shown in FIG. 12A. That is, when the LCD control circuit 3 outputs to the column drivers 5-6 and the segment drivers 8-9, it outputs the AC pulse control signal M ₀ as the modified AC pulse control signal M shifted by the time t _M. As a result, as in the case where the pulsed display-off control signal DSPOFF according to the first embodiment of the present invention is output due to the shift of the AC conversion timing, regardless of the display data, FIG.
As shown in (D), all are AC components, and the pixel applied voltage (voltage between A and C in FIG. 18) is substantially the ground voltage GND, and the difference in effective voltage (voltage between A and B in FIG. 18) of each pixel is almost equal. Disappear. As the LCD driving method of the second embodiment, the shift time t _M of the display voltage V ₀ and the modified AC pulse control signal _M is (-19.01 V, 10 μs), (-20.
02V, 20 μs) and (−20.99 V, 30 μs) were tested. As a result, no ghost display or image unevenness as shown in FIG. The display result is as follows. In particular, the shift time t of the modified AC pulse control signal M
_M is half of the selective drive time T _S = 64 μs, t _M = 32 μ
The display image quality improved as the value of s approached. This is
It is considered that the increase in the shift time promotes the alternating current of the voltage (AC in FIG. 18) applied to the liquid crystal pixels, and the effective voltage difference between the pixels is reduced.

FIG. 13 is a characteristic diagram showing the relationship between the display voltage V ₀ , the shift time t _{M of the} modified AC pulse control signal _M and the contrast according to the LCD driving method of the second embodiment.
In the LCD driving method according to the second embodiment of the present invention, the contrast decreases as the shift time t _M increases. As a third embodiment of the present invention, as a method for solving such a problem that the contrast is lowered, FIG. 14 illustrates a drive voltage waveform in which the drive voltage waveform is improved by the LCD drive method of the second embodiment. The modified AC pulse control signal M of FIG. 14A is obtained by delaying the AC pulse control signal M ₀ similar to that shown in FIG. 12A by the shift time t _M. When the shift time t _M of the modified AC pulse control signal M is increased, the off time w of the voltage applied to the liquid crystal element is increased and the DC component is decreased, so that the crosstalk is decreased. At this time, since the voltage polarity is reversed at the time of selection, the liquid crystal element is not sufficiently charged and the contrast is lowered. The broken line shows the drive voltage waveform in the LCD drive method of the second embodiment. In the third embodiment _{, the} LCD control circuit 3 is controlled so as to be the non-selection potential for the shift time t _{M of the} modified AC pulse control signal M, and the potential of the remaining selection time (T _S −t _M ) is indicated by the solid line. As shown in, raise the battery to fully charge the liquid crystal element. FIG. 15 shows the third aspect of the present invention.
FIG. 14 is a contrast characteristic diagram corresponding to FIG. 13 according to the LCD driving method of the embodiment. The horizontal axis in FIG. 15 represents the duty in place of the shift time t _M shown _in FIG. 13, but there is no reduction in contrast even at the duty = 400 corresponding to the shift time t _M = 30 μs in FIG. It can be seen from the examples that the contrast is improved.

A fourth embodiment of the LCD driving method of the present invention will be described with reference to FIG. The LCD driving method of the fourth embodiment is the LCD control circuit 3 and the column driver 5 shown in FIG.
˜6, the output frequency of the display data (FIG. 16C) is doubled so that substantially the same result as described above can be obtained without changing the segment drivers 8 to 9 as described above. The data to be originally displayed is displayed in the first frequency part, and the data opposite to that is continued in the second frequency part. For example, for an LCD device displaying white (W), white (W) data is continued in the first frequency part, and black (B) data, which is the reverse of white data, is continued in the second frequency part. The alternating pulse control signal M ₀ is the same as the conventional one, and the display off control signal DSPOFF is not used. By doubling the output frequency of the display data in this way, it is substantially equivalent to the shift time t _M of the AC pulse control signal M ₀ in the second embodiment being half the selective drive time T _S. The result is obtained. The display result was the same as that shown in FIG. 10 with no display unevenness or ghost display.

In the above embodiment, the liquid crystal element has a non-linear M
Although the example using the IM element has been described, the same result as above can be obtained when a back-to-back type liquid crystal element is used as another nonlinear liquid crystal element.
Alternatively, the LCD driving method of the present invention is not limited to the non-linear liquid crystal element, but can be applied to a simple matrix type STN-LCD. Although the above embodiments have been described with respect to two-color display examples of white and black, the present invention can be applied to a color LCD device.

[0022]

As described above, according to the present invention, 1
The display data can be displayed by a simple method of forcibly bringing the liquid crystal element into a non-selected state regardless of whether the liquid crystal element is selected or not selected for a predetermined period of the selective drive time (period) of the cycle. Regardless of this, AC driving of each pixel becomes possible, and as a result, the effective voltage difference of each pixel is almost eliminated, the difference in liquid crystal light transmittance becomes small, ghost display due to crosstalk does not occur, and the display image quality is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an LCD driving device for implementing an LCD driving method of the present invention.

FIG. 2 is a circuit configuration diagram of the column driver of FIG.

3 is a liquid crystal element drive voltage generation circuit diagram in the column driver of FIG.

FIG. 4 is a diagram showing a relationship between a liquid crystal element drive voltage and an operating state of the liquid crystal element.

FIG. 5 is a pixel voltage waveform diagram.

FIG. 6 is a timing diagram of LCD driving signals in a conventional LCD driving method.

FIG. 7 is a timing diagram of LCD drive signals in the LCD drive method according to the first embodiment of the present invention.

FIG. 8 is a diagram showing reference display contents on a liquid crystal panel used for evaluation of an LCD driving method.

9 is a diagram showing a display result on a liquid crystal panel based on the conventional LCD driving method shown in FIG.

10 is a diagram showing a display result on a liquid crystal panel based on the LCD driving method of the first embodiment of the present invention shown in FIG.

FIG. 11 is an LCD driving signal timing diagram in a conventional LCD driving method for comparison with the LCD driving method of the second embodiment of the present invention.

FIG. 12 is an LCD drive signal timing in the LCD drive method according to the second embodiment of the present invention.

FIG. 13 is a contrast characteristic diagram according to the LCD driving method of the second embodiment of the present invention.

FIG. 14 is an LCD drive signal timing diagram in the LCD drive method of the third embodiment of the present invention.

FIG. 15 is a contrast characteristic diagram in the LCD driving method according to the third embodiment of the present invention.

FIG. 16 is a timing diagram of LCD drive signals in the LCD drive method according to the fourth embodiment of the present invention.

FIG. 17 is an equivalent circuit diagram of a MIM liquid crystal panel used for evaluation of an LCD driving method.

[Explanation of symbols] 1 ... Liquid crystal panel, 3 ... LCD control circuit, 5-6 ...
Column driver, 8-9 ... segment driver, DSPOFF ... display off control signal, M ₀ ... AC pulse control signal, M ... modified alternating pulse control signal.

Claims (5)

[Claims] 1. A full-selection drive timing in a liquid crystal display device driving method in which an alternating voltage is applied to a liquid crystal element from a column and a segment direction to selectively drive a liquid crystal panel in which a plurality of liquid crystal elements are arranged in a matrix. With regard to the above, all liquid crystal elements in the liquid crystal panel are forcibly set to the non-selected state regardless of whether the liquid crystal element is selectively driven for a predetermined time, whether the liquid crystal element is selected or not selected. Liquid crystal display device driving method. 2. A voltage for alternately deactivating a liquid crystal element within a time period for selectively driving one liquid crystal element so that an equal voltage is applied to both ends of the liquid crystal element when the liquid crystal element is in the forced non-selected state. 2. The liquid crystal display device driving method according to claim 1, wherein a pulse voltage having a level is applied to the liquid crystal element from the column and segment directions. 3. An alternating pulse control signal having a frequency defining a time for selectively driving one liquid crystal element to apply an alternating voltage to the liquid crystal panel is determined within a half of the selective drive time from a normal timing. The method for driving a liquid crystal display device according to claim 1, wherein the liquid crystal display device is shifted by time. 4. The method of driving a liquid crystal display device according to claim 3, wherein the liquid crystal element is brought into a non-selected state for a time corresponding to a shift of the AC pulse control signal for a predetermined time. 5. As display data for driving one liquid crystal element, data to be displayed on the liquid crystal element during one line period and data having an inverse logic to the display data are continuously added,
A method for driving a liquid crystal display device, wherein one liquid crystal element is applied with a frequency twice as high as that for selective driving, and the liquid crystal element is driven with a frequency twice as high.