JPH11237606A - Driving method of liquid crystal display device and liquid crystal display device using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a uniform in-surface luminance distribution and excellent contrast. SOLUTION: In a 1st field, odd-numbered scanning lines are scanned in order from the top to the bottom in a write period 101, displayed in a display period 102 and reset together in a reset period 103. In a 2nd field, even-numbered scanning lines are scanned in order from the top to the bottom in the write period 101, displayed in the display period 102 and reset together in the reset period 103. Since the period from the writing to the resetting is made uniform in a display panel surface, a uniform in-surface luminance distribution is obtained and a flicker is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for driving a liquid crystal display and a liquid crystal display.

[0002]

2. Description of the Related Art Currently, the mainstream of high-performance liquid crystal displays is a TN (twisted nematic) mode or IPS (in-plane switching) mode TFT (thin film transistor) type active matrix liquid crystal display device using a nematic liquid crystal. In these active matrix liquid crystal display devices, the image signal is usually 30H.
Rewriting is performed at 60 Hz to write positive and negative at z, and the time for one field is about 16.7 ms (millisecond). Here, the total time of both positive and negative is called one frame, and is about 33.3 ms. On the other hand, the response time of the current liquid crystal is about this frame time even at the fastest response speed. For this reason, when displaying a video signal composed of a moving image or displaying a high-speed computer image,
A response speed faster than the current frame time is required.

On the other hand, in order to further increase the definition of the liquid crystal display device, a field-sequential color liquid crystal display device that temporally switches a backlight, which is illumination light of the liquid crystal display device, to red, green, and blue has been studied. . In this method, there is no need to spatially dispose the color filters, so that it is possible to achieve three times higher definition than in the past. In a field sequential liquid crystal display device, 1/3 of one field
, It is necessary to display one color, and the time available for display is about 5 ms. Therefore, a response time shorter than 5 ms is required for the liquid crystal itself. Use of a liquid crystal having spontaneous polarization, such as a ferroelectric liquid crystal or an antiferroelectric liquid crystal, has been studied as a liquid crystal capable of realizing such a high-speed response. Also, with regard to nematic liquid crystals, studies have been made to increase the speed by increasing the dielectric anisotropy, decreasing the viscosity, reducing the film thickness, or changing the liquid crystal alignment to a pie-type alignment or the like.

In an active matrix liquid crystal display device, the time during which voltage and charge are actually written to the liquid crystal portion is only the selection time (writing time) of each scanning line. This time is 16.7 μs (microsecond) in the case of a liquid crystal display device having 1000 lines and writing in one field time, and about 5 μs in the case of performing field sequential driving. At present, there are almost no liquid crystal elements or liquid crystal usage forms in which the response is completed within such a time. There is no known liquid crystal element having the above-mentioned spontaneous polarization or a high-speed nematic liquid crystal which has such a fast response. As a result, the following problem occurs. That is, the response of the liquid crystal usually occurs after the completion of the signal writing. As a result, in a liquid crystal having spontaneous polarization, an anti-electric field is generated by rotation of the spontaneous polarization, so that the voltage across the liquid crystal layer sharply decreases. For this reason,
The voltage written to both ends of the liquid crystal layer changes greatly. On the other hand, even in a high-speed nematic liquid crystal, the change in capacitance of the liquid crystal layer due to the anisotropy of the dielectric constant becomes extremely large, so that the holding voltage to be written and held in the liquid crystal layer changes. Such a decrease in the holding voltage, that is, a decrease in the effective applied voltage causes insufficient writing and lowers the contrast of the screen.

[0005] Japanese Applied Physics, Vol. 36, part 1, number 2, pp. 720-72
On page 9, it is described that a phenomenon called "step response" is observed when the same image signal is continuously written over several frames from the frame in which the image signal has changed and the absolute value of the signal voltage has changed. ing. This phenomenon is a phenomenon in which the transmittance fluctuates between light and dark for each field over several frames for the same signal voltage, and stabilizes at a constant transmitted light amount after several frames.

An example of the above phenomenon will be described with reference to the schematic diagram of FIG. FIG. 7A is a waveform diagram of the data voltage, and FIG. 7B is a waveform diagram of the transmittance at that time. When the data voltage shown in FIG. 16A is applied to the liquid crystal, the transmittance vibrates in a bright and dark manner for each field as shown in FIG. 16B. In the example shown here, the transmittance is finally constant at the fourth frame. Calm down. As described above, since several frames are required for the actual transmittance change, the high-speed display image is lost.

The transmittance after the liquid crystal response is determined not by the applied signal voltage but by the amount of charge stored in the liquid crystal capacitance after the liquid crystal response. This charge amount is determined by the accumulated charge before writing the signal and the newly written charge. The accumulated charge after the response also changes depending on the pixel design values such as the physical constants of the liquid crystal, the electrical parameters, and the storage capacitance. Therefore, the correspondence between the signal voltage and the transmittance is as follows: (1) the correspondence between the signal voltage and the write charge;
(2) Accumulated charge before writing, (3) Information for calculating accumulated charge after response and actual calculation are required. As a result, a frame memory for storing (2) over the entire screen and a calculation unit (1) or (3) are required. This undesirably increases the number of parts of the system.

As a method of solving the above problem, a reset pulse method of applying a reset voltage for adjusting a liquid crystal state to a predetermined liquid crystal state before writing new data is often used.
According to the reset pulse method, a new data is always written in a predetermined state, so that there is a one-to-one correspondence between the written signal voltage and the obtained transmittance. This one-to-one correspondence simplifies the method of generating the driving signal and eliminates the need for a means such as a frame memory for storing the previous write information.

As another method of applying the reset voltage, positive and negative data signal voltages are generated for a given image signal, a negative (positive) voltage is applied after a positive (negative) voltage is applied, and thereafter, A method of applying a reset voltage is also used.
In this case, if the positive and negative data signal voltages having the same amplitude are simply applied, the above-mentioned “step response” occurs. Therefore, a data signal voltage having a waveform shown in FIG. 17A is applied. FIG. 17B is a waveform diagram of the transmittance obtained at that time. The waveform shown by the dotted line in the figure is the waveform of the data voltage when the amplitude is equal between positive and negative,
And a transmittance waveform when the waveform is applied.

To prevent the "step response", FIG.
As shown in (a), the amplitude of the data voltage in the first half of the frame (here, the positive data voltage) is set to be low, and the amplitude of the data voltage in the second half of the frame (here, the negative data voltage) is set to be the same as the dotted waveform. I do. As a result, the step response is prevented, and the same transmittance is obtained in the first half and the second half of the frame as shown in FIG. By performing a reset at the end of the subsequent frame, the liquid crystal is aligned in a state where a predetermined reset has been performed. In the next frame, a one-to-one correspondence of a constant signal voltage and a constant transmittance can be obtained by newly applying the same waveform.

[0011]

In the conventional reset pulse method, whichever of the above reset pulse methods is adopted,
The following problems exist. That is, first, there is a problem that the luminance greatly changes depending on the location in the screen in accordance with the reset timing. For example, in the case of sequentially scanning from the upper part of the screen to the lower part, if the reset is performed after the completion of the scanning of all the lines, the display time after writing of almost one field can be obtained in the upper part of the screen, while the writing time in the lower part of the screen is obtained The reset is performed later with only a short display time. This phenomenon will be described with reference to FIG.

FIG. 14A shows a writing (scanning) period 101,
FIG. 3 is a diagram schematically illustrating a state of each of a display period 102 and a reset period 103 in a two-dimensional manner based on a screen scanning direction and a time axis. In this figure, it has eight scanning lines, and scanning is performed sequentially from the upper part to the lower part of the screen in the writing period 101,
A reset period 103 is reached after a certain display period 102, indicating that the entire screen is reset at once. FIG.
(B) schematically shows the scanning line voltage and transmittance at the top of the screen, that is, on the first (first) scanning line when white display is performed using such a driving method. Also,
FIG. 14C schematically shows the scanning line voltage and transmittance at the bottom of the screen, that is, on the eighth (eighth) scanning line. In the first scanning line, white display can be obtained in a relatively long period excluding the reset period and the rising period of the response from one frame period. However, in the eighth scanning line, the reset starts immediately after the response ends. , Almost no white display is obtained. As a result, when the same signal is displayed, FIG.
As shown in (b), when viewed over the entire frame period, a phenomenon occurs in which the upper part of the screen is bright and the lower part of the screen is dark. Such an in-plane distribution significantly reduces image quality.

Next, since there is always a period during which a predetermined display state is set, there is a problem that the overall contrast and the maximum transmittance are reduced. For example, when a black display state is obtained by resetting, the period during which a predetermined display other than black display is obtained is smaller than when no reset is performed, and the maximum transmittance and the transmittance of each gradation are reduced. on the other hand,
When the state other than the black display is set by the reset, the transmittance at the time of the reset is added during the black display and averaged over time, so that the transmittance of the black display increases and the contrast decreases.

Further, since there is always a period in which the transmittance is constant, there is a problem that flicker occurs between the transmittance and another display transmittance. For example, when resetting the entire screen at the same time, the entire screen flickers at the same time, so that flicker is strongly recognized.

Further, there is a problem that the scanning period is shortened by the reset period. Normally, scanning period (writing time)
Is approximately equal to the field time, which is half the frame time, divided by the number of scan lines. However, if the reset period is provided during the field time, FIG.
The scanning period 101 shown in (a) is obtained by dividing the field time minus the reset time 103 by the number of scanning lines (8). As a result, the scanning period becomes shorter. As a means for solving the problem that the reset period affects the scanning period, a method of combining interlace driving and reset is described in, for example, Japanese Patent Application Laid-Open No. 4-186217. In this method, an FLC (ferroelectric liquid crystal) panel is driven in an interlace mode, and a scanning line in a non-display period is reset. This prevents a reduction in the scanning period due to the reset period. Further, since the reset cycle of the adjacent lines is shifted, it is considered that flicker is reduced by averaging. However, even this method does not improve other problems, such as a decrease in in-plane luminance distribution and maximum transmittance.

In view of the above, it is an object of the present invention to provide a liquid crystal display device having a high response speed, a small variation in in-plane luminance and little flicker, and a high contrast and high luminance can be obtained even when a reset pulse is used. Is to provide a way.

Another object of the present invention is to provide a high-contrast, high-brightness liquid crystal display device using the above-described driving method, which has a high response speed, has less in-plane variation of luminance and has less flicker.

[0018]

In order to achieve the above object, a liquid crystal driving method according to the present invention provides a liquid crystal display for sequentially scanning scanning lines for each field to display a screen and subsequently resetting the scanning lines. In the driving method of the device, the scanning lines are sequentially scanned in the first field, and then reset at once,
It is characterized in that, in the second field following the first field, scanning is performed in the reverse order of the scanning order in the first field, and then reset simultaneously.

According to the liquid crystal driving method of the present invention, since the time from writing to reset is averaged in the plane of the display panel, a uniform in-plane luminance distribution can be obtained.

When interlaced driving is performed by the driving method of the present invention, odd-numbered scanning lines are sequentially scanned, for example, from top to bottom in the first frame, and even-numbered scanning lines are scanned from bottom to top in the second frame. It is preferable to scan sequentially.

When interlaced driving is performed, it is a preferable embodiment of the present invention that one frame has two writing periods and one reset line has two reset periods in one frame. Here, in one frame, one scanning line has one reset period, and one frame after the reset is performed.
The configuration can be such that the absolute value of the data signal voltage at the time of the second writing is smaller than the absolute value of the data signal voltage at the time of the second writing.

The liquid crystal display device of the present invention is a liquid crystal display device employing the above-described liquid crystal driving method of the present invention, and can provide actions and effects corresponding to the method of the present invention.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings based on embodiments of the present invention. FIG.
FIG. 4 is a diagram for illustrating a driving method according to the first embodiment of the present invention, and FIG. 4A is a time chart illustrating a configuration of time distribution for each scanning line. The horizontal axis is the time axis, and the vertical axis is the scanning line axis. This figure shows an example of eight scanning lines. FIG. 3B is a time chart showing the scanning line voltage and the transmittance of the first (first) scanning line in FIG. 3A, and FIG. 3C is the eighth (final) scanning line. 4 is a time chart showing a scanning line voltage and a transmittance of a scanning line.

In this embodiment, in the writing period 101, after each scanning line is sequentially selected and data is written,
The display shifts to the display period 102, and the display is performed. Subsequently, in the reset period 103, all the scanning lines are simultaneously reset.
Here, the scanning order of the scanning lines is different between the first field and the second field in one frame. That is, the first
In the field, scanning is performed sequentially from top to bottom from the first scanning line to the eighth scanning line, and in the second field, from the eighth scanning line to the first scanning line, from bottom to top. Scan. Note that the scanning order of the first field and the second field may be reversed.

As shown in FIG. 1B, in the first scanning line, a scanning signal for writing is applied at the beginning of the first field, and a scanning signal for reset is applied at the end of the field. On the other hand, in the second field, a scanning signal for writing is applied at the end, and a scanning signal for reset is applied at the end of the field. On the other hand, as shown in FIG. 1C, on the eighth scanning line, a scanning signal for writing is applied at the end of the first field, and a scanning signal for reset is applied at the end of the field. On the other hand, in the second field, a scanning signal for writing is applied at the initial stage, and a scanning signal for reset is applied at the end of the field. In the examples shown in FIGS. 1B and 1C, the write signal is a signal for white display (high transmittance) and is a signal for black display (low transmittance) at the time of reset. The transmittance itself differs depending on the actual write data.

In the first scanning line, the transmittance starts to increase from the beginning of the first field, reaches the maximum transmittance after the end of writing, and reaches the minimum transmittance in the reset period at the end of the field. On the other hand, in the second field, the transmittance starts to increase at the end of the period, reaches the maximum transmittance after the writing is completed, and reaches the minimum transmittance in the reset period immediately thereafter. On the other hand, the eighth
In the number-th scanning line, the transmittance starts to increase from the end of the first field, reaches the maximum transmittance after the end of the writing, and reaches the minimum transmittance in the reset period immediately thereafter. On the other hand, in the second field, on the contrary, the transmittance starts to increase at the initial stage, reaches the maximum transmittance after the end of the writing, and reaches the minimum transmittance in the reset period at the end of the field.

FIG. 2A is an in-plane luminance distribution diagram at each moment of the liquid crystal display panel in the example shown in FIG.
The screens 1A, 1B, and 1C correspond to the times indicated by the same reference numerals in FIG. 1A, respectively, and indicate the initial writing time of the first field, the latter writing time, and the first writing time.
Each luminance distribution at the end of the field is shown. The screens 1D, 1E, and 1F correspond to the points indicated by the same reference numerals in FIG. 1A, respectively, and indicate the initial writing time of the second field, the latter writing time, and
Each luminance distribution at the end of the second field is shown. FIG. 2B is a luminance distribution actually observed, that is, a luminance distribution averaged over a frame time. As shown in FIG. 2 (a), corresponding to the transmittance change of FIG. 1 (c), the upper part of the panel becomes brighter than the lower part in 1A and 1B of the first field, and the lower part of the panel in 1D and 1E of the second field. Brighter than the top. In the last fields 1C and 1F, the first and second fields display black. As described above, although the in-plane luminance distribution is large at each moment, these luminances are averaged over time.
As can be understood from (b), the difference in the in-plane luminance distribution is averaged, and the observed in-plane luminance is uniform.

FIGS. 3A to 3C respectively show a second embodiment of the present invention.
2 is a time chart showing the embodiment of the present invention in the same display method as in FIGS. 1 (a) to 1 (c). In the present embodiment, the first
Bidirectional scanning is performed in the same manner as in the first embodiment, but differs from the first embodiment in that the arrangement of the reset periods is different and that the interlace driving is performed. In the present embodiment, half (odd number) of all eight scanning lines are scanned (selected) in the first field, and the remaining half (even number) are scanned in the second field. The reset period 103 in each scanning line is arranged at the end of the non-scanning (selection) field. In other words, the odd-numbered scanning lines have a writing period 101 in the first field, write sequentially by scanning from the top, write is performed, a display period 102 follows, and a reset period 103 is provided at the end of the second field. Can be On the other hand, for the even-numbered scanning lines, a reset period 103 is provided at the end of the first field, a writing period 101 is provided in the second field, writing is performed by scanning sequentially from the bottom, and then a display period 102 is continued. , The next reset period is provided at the end of the first field of the next frame (not shown).

In the first field, odd-numbered scanning lines are sequentially scanned from the top, and in the second field, even-numbered scanning lines are sequentially scanned from the bottom. That is, in the first scanning line, a scanning signal for writing is applied at the beginning of the first field, and a scanning signal for reset is applied at the end of the second field. For this reason, the transmittance starts increasing from the beginning of the first field, reaches the maximum transmittance after the end of the writing, and reaches the minimum transmittance in the reset period at the end of the second field. On the other hand, on the eighth scanning line, a reset scanning signal is applied at the end of the first field,
A scan signal for writing is applied at the beginning of the second field. Therefore, the transmittance becomes minimum at the end of the first field, starts to increase at the beginning of the second field, and reaches the maximum transmittance after the end of writing.

FIGS. 4A and 4B show the luminance distribution of the second embodiment in the same manner as FIGS. 2A and 2B, respectively. The screens 2A to 2F in FIG.
Corresponds to each time point indicated by the same reference numeral. FIG.
As shown in (a), corresponding to the transmittance change of FIG. 3 (c), in the first field, the even-numbered scanning lines are always bright in the initial and later stages of writing, and the odd-numbered scanning lines are in the upper part of the panel. Brighter than the bottom. On the other hand, in the second field,
The odd-numbered scanning lines are always bright in the initial and late stages of writing, and the even-numbered scanning lines are brighter at the bottom of the panel than at the top.
Also, at the end of the field, in the first field, the even-numbered scanning lines become black and the odd-numbered scanning lines become white, and in the second field, the odd-numbered scanning lines become black and the even-numbered scanning lines become white. . As described above, although the in-plane luminance distribution is large at each moment, as can be understood from FIG. 4B in which this characteristic is averaged over time, the difference in the in-plane luminance distribution is greatly reduced. Here, although bright and dark fringes are generated at the upper and lower parts of the panel corresponding to the scanning lines, these fringes hardly occur at the central part of the panel. In an actual screen, since the pitch of the scanning lines is fine, the light and dark fringes are spatially averaged to obtain a substantially uniform display over the front surface of the panel.

The second embodiment has an advantage that the luminance is extremely higher than the luminance of the first embodiment shown in FIG. 2B. Furthermore, since flicker occurs for each of the odd and even lines of the interlaced drive, averaging between the lines reduces the observed flicker. Further, the fact that there is no period during which the entire screen is displayed in black is also effective in reducing flicker.

FIGS. 5A to 5C respectively show a third embodiment of the present invention.
2 is a time chart showing the embodiment of the present invention in the same display method as in FIGS. 1 (a) to 1 (c). In the present embodiment, bidirectional scanning is performed by interlaced driving as in the second embodiment, and corresponds to a driving method in which the frame frequency is doubled in the second embodiment. That is, as shown in FIG. 2A, the odd-numbered scanning lines have a writing period 101 in the first half of the first field, and are sequentially scanned and written from the top, followed by a display period 102. At the end of the field, a reset period 103 is provided. The second field is similarly time-distributed. On the other hand, even-numbered scanning lines are provided with a reset period 103 at the end of the first half of the first field,
There is a writing period 101 in the latter half of the field, scanning is performed sequentially from the bottom, and a display period 102 follows thereafter. The second field is similarly time-distributed, after which a reset period is provided at the end of the first half of the first field of the next frame (not shown).

As shown in FIG. 5B, the first scanning line has a writing scanning signal at the beginning of the first field, a reset scanning signal at the end of the first field, and a scanning signal at the end of the second field. A scanning signal for writing is applied at the beginning, and a scanning signal for reset is applied at the end of the second field. As a result, the transmittance starts to increase from the beginning of the first field, reaches the maximum transmittance after the end of writing, reaches the minimum transmittance during the reset period at the end of the first field, and starts increasing from the beginning of the second field. Reaches the maximum transmittance after the end of the writing, and reaches the minimum transmittance in the reset period at the end of the second field. On the other hand, the eighth scanning line is shown in FIG.
As shown in (c), a scanning signal for resetting at the end of the first half of the first field, a scanning signal for writing at the beginning of the second half of the first field, a scanning signal for resetting at the end of the first half of the second field, Scanning signals for writing are respectively applied at the beginning of the latter half of the second field. Thereby, the first
At the end of the first half of the field, the transmittance becomes the minimum, the transmittance starts to increase in the second half of the first field, reaches the maximum transmittance after the end of writing, reaches the lowest transmittance at the end of the first half of the second field, and becomes early in the second half of the second field. The transmittance starts to increase and reaches the maximum transmittance after the end of writing.

FIG. 8A is a luminance distribution actually observed in the third embodiment and averaged over a frame time. The in-plane luminance distribution seen by the conventional driving method of FIG. 15B is reduced. In the present embodiment, since two reset periods are provided between one frame, high luminance as in the second embodiment cannot be obtained. Other features are the same as those of the second embodiment, but the electrical asymmetry is greatly different. In the writing according to the first embodiment of FIG. 1, the lengths of the display periods 102 of the first field and the second field are often different. This is because, in the case of a liquid crystal having spontaneous polarization such as a ferroelectric liquid crystal or an antiferroelectric liquid crystal, electric asymmetry due to an anti-electric field where polarization occurs is apt to occur, and causes such as image sticking due to ions. Become. In the writing of the second embodiment shown in FIG. 3, since there is only one writing in one frame, an electrical asymmetry occurs according to the polarity of the data signal. On the other hand, in the present embodiment, the display periods of the first field and the second field are different.
Since the length of the data 102 is the same and data signals of both polarities can be written corresponding to each field, there is no electrical asymmetry and no burn-in occurs.

FIGS. 6A to 6C are time charts showing the fourth embodiment in the same manner as FIGS. 1A to 1C. In this embodiment, interlaced driving and bidirectional scanning are performed as in the second and third embodiments, but interlaced driving is performed in a field, and the fields are in a bidirectional scanning relationship. This is different from the preceding embodiments in the point. That is, the odd-numbered scanning lines have a writing period 101 in the first half of the first field and sequentially scan from the top, followed by a display period 102,
At the end of the first field, a reset period 103 is provided. Next, during the first half of the second field, the writing period 101
Scanning is performed sequentially from the bottom, followed by a display period 102, and a reset period 103 is provided at the end of the second field. On the other hand, the even-numbered scanning lines are provided with a reset period 103 at the end of the first half of the first field, have a writing period 101 in the latter half of the field, and are sequentially scanned from the top, followed by a display period 102. Subsequently, a reset period 103 is provided at the end of the first half of the second field, and a writing period 101 is provided in the second half of the field, and scanning is sequentially performed from the bottom,
Thereafter, a display period 102 follows, and a reset period is provided at the end of the first half of the first field of the next frame (not shown).

In the first scanning line, as shown in FIG. 6B, a scanning signal for writing is generated at the beginning of the first field.
At the end of the first field, the reset scanning signal is
A scan signal for writing is applied at the end of the field, and a scan signal for reset is applied at the end of the second field.
As a result, the transmittance starts to increase from the beginning of the first field, reaches the maximum transmittance after the end of writing, reaches the minimum transmittance during the reset period at the end of the first field, and increases from the end of the first half of the second field. At first, the maximum transmittance is reached after the end of the writing, and becomes the minimum transmittance in the reset period at the end of the second field. On the other hand, in the eighth scanning line, as shown in FIG. 6C, a reset scanning signal is provided at the end of the first half of the first field, and a writing scan signal is provided at the end of the second half of the first field. A scanning signal for reset is applied at the end of the first half of the field, and a scanning signal for writing is applied at the beginning of the second half of the second field. Thereby, as shown in FIG. 6C, the transmittance becomes minimum at the end of the first half of the first field, starts to increase at the end of the second half of the first field, reaches the maximum transmittance after the end of writing,
At the end of the first half of the second field, the transmittance becomes minimum,
The transmittance starts to increase in the latter half of the field, and reaches the maximum transmittance after the writing is completed.

FIG. 8B shows a luminance distribution actually observed in the present embodiment and averaged over time over a frame time. In the present embodiment, the in-plane luminance distribution seen in the conventional driving method of FIG. 15B and the third embodiment of FIG. 8A is eliminated. As a result, the light and dark stripes observed in the second and third embodiments are not generated. Also, unlike the first embodiment shown in FIG. 2B in which there is no luminance distribution in the plane, flicker occurs for each of the odd and even lines of the interlace drive. Flicker is reduced. Further, the fact that there is no period during which the entire screen is displayed in black is also effective in reducing flicker. Further, since the substantial frequency is higher than that of the first embodiment shown in FIG. 1, the difference between the display periods of the first field and the second field is half that of the first embodiment. At the same time, it is possible to write twice in one frame. As a result, the difference in the length of the display period 102 between the first field and the second field is small, and data signals of both polarities can be written corresponding to each field. Less occurrence.

FIGS. 7A to 7C respectively show a fifth embodiment of the present invention.
2 is a time chart showing the embodiment example in the same manner as FIGS. 1 (a) to 1 (c). In this embodiment, bidirectional scanning is performed by interlaced driving as in the second to fourth embodiments, but interlaced driving and bidirectional scanning are performed in a field, and fields are also bidirectionally scanned. It has a scanning relationship. In other words, the odd-numbered scanning lines have a writing period 101 in the first half of the first field and scan sequentially from the top, followed by a display period 102, and a reset period 103 at the end of the field. Next, there is an address period 101 in the first half of the second field and scanning is performed sequentially from the bottom, followed by a display period 102, and a reset period 103 is provided at the end of the field. On the other hand, an even-numbered scanning line is provided with a reset period 103 at the end of the first half of the first field, has a writing period 101 in the latter half of the field, is scanned sequentially from the bottom, and is followed by a display period 102. Next, at the end of the first half of the second field, the reset period 103
Is provided, there is a writing period 101 in the latter half of the field and scanning is performed sequentially from the top, followed by a display period 102,
At the end of the first half of the first field of the next frame (not shown), a reset period is provided.

In the first scanning line, as shown in FIG. 7 (b), a scanning signal for writing at the beginning of the first field is
At the end of the first field, the reset scanning signal is
A scan signal for writing is applied at the end of the field, and a scan signal for reset is applied at the end of the second field.
As a result, the transmittance starts to increase from the beginning of the first field, reaches the maximum transmittance after the end of writing, reaches the minimum transmittance during the reset period at the end of the first field, and increases from the end of the first half of the second field. At first, the maximum transmittance is reached after the end of the writing, and becomes the minimum transmittance in the reset period at the end of the second field. On the other hand, in the eighth scanning line, as shown in FIG. 7C, the scanning signal for resetting at the end of the first half of the first field, the scanning signal for writing at the beginning of the second half of the first field, A scanning signal for reset is applied at the end of the first half of the field, and a scanning signal for writing is applied at the end of the second half of the second field. As a result, the transmittance becomes the lowest at the end of the first half of the first field, the transmittance starts to increase at the beginning of the latter half of the first field, reaches the maximum transmittance after the end of the writing, and becomes the lowest at the end of the first half of the second field. The transmittance starts to increase at the end of the latter half of the two fields, and reaches the maximum transmittance after writing is completed. The luminance distribution diagram in the panel surface, which is actually observed in the present embodiment and is time-averaged over the frame time, is the same as FIG. 8B showing the fourth embodiment. Other features are the same as those of the fourth embodiment.

FIG. 9A is a time chart showing a sixth embodiment of the present invention in the same manner as FIG. 1A. In this embodiment, bidirectional scanning is performed by interlace driving as in the second to fifth embodiments.
This is the scanning timing when the data signal voltage indicated by is used, and differs from the previous embodiment in that two writing periods 101 and one reset period 103 exist in one frame. That is, the odd-numbered scanning lines have the writing period 101 in the first half of the first field, scan sequentially from the top, and then the display period 102 follows. Next, there is a writing period 101 in the first half of the second field, and scanning is performed sequentially from the top, followed by a display period 102, and a reset period 103 is provided at the end of the field. On the other hand, the even-numbered scanning lines are provided with a reset period 103 in the middle of the first field, a writing period 101 in the latter half of the field, and are sequentially scanned from the bottom, followed by a display period 102. Then
During the latter half of the second field of the second field, there is a writing period 101, which is scanned sequentially from the bottom, followed by a display period 102, and a reset period is provided in the middle of the first field of the next frame (not shown).

FIG. 9B shows a luminance distribution actually observed in the present embodiment and averaged over time over a frame time. Although the in-plane luminance distribution seen by the conventional driving method of FIG. 15B is alleviated, bright and dark fringes are generated at the upper and lower portions of the panel corresponding to the scanning lines. In the center of the panel, this stripe hardly occurs. When the pitch of the scanning lines is fine, the light and dark stripes are spatially averaged, and a substantially uniform display is obtained over the entire panel. In addition, the luminance is extremely higher than that of the conventional FIG. 15B and FIG. 2B of the first embodiment. Further, compared to the second embodiment, a higher luminance can be obtained because the time from the reset period to the next writing period is shorter. Furthermore, since flicker occurs for each of the odd and even lines of the interlaced drive, the average of the lines reduces the observed flicker. Also, the fact that there is no period during which the entire screen is displayed in black is effective in reducing flicker.

FIG. 9C is a time chart showing a seventh embodiment of the present invention, similarly to FIG. 1A. The present embodiment is almost the same as the sixth embodiment, except that the scanning direction of the second field is different, and the same interlace driving and bidirectional scanning as in the second to fifth embodiments are performed. . That is, the odd-numbered scanning lines have the writing period 101 in the first half of the first field, scan sequentially from the top, and then the display period 102 follows. Next, there is an address period 101 in the first half of the second field and scanning is performed sequentially from the bottom, followed by a display period 102, and a reset period 103 is provided at the end of the field. On the other hand, the even-numbered scanning lines are provided with a reset period 103 in the middle of the first field, a writing period 101 in the latter half of the field, and are sequentially scanned from the bottom, followed by a display period 102. continue,
In the latter half of the second field, there is an address period 101, which is scanned sequentially from the top, followed by a display period 102, and a reset period is provided in the middle of the first field of the next frame (not shown). The time-averaged luminance distribution of the panel is the same as that in FIG. 9B of the ninth embodiment.

FIG. 10A is a time chart showing an eighth embodiment of the present invention. In the present embodiment, it is assumed that field sequential display is performed, and in addition to the time chart of FIG. 1A, the luminance incident on the light source panel is shown as one of the vertical axes. The light source is scanned in this order in red, green, and blue. In addition,
This order can be arbitrarily exchanged in correspondence with the exchange of data signals. The light source does not enter the panel during the scanning line reset period, and this period is a period for switching to another color. For scanning, see FIG.
Is the same as the scan timing when the data signal voltage is used, but because of the field sequential display,
There are three reset periods 103 in one frame. During scanning of each color, two writing periods 101 are provided, and positive and negative data signals are distributed and applied to each writing period for each code. After the two writings, a reset period 103 is provided. The set consisting of two writings and one reset is repeated three times in synchronization with each color. As a result of scanning of these light sources and scanning lines, information of each color is displayed in one frame, and color display can be performed in units of one pixel. Since the number of times of the reset period is half as compared with the case where the field sequential display is performed by repeating the driving method of FIG. 14 three times, a display with high luminance can be performed. The observed in-plane luminance distribution is shown in FIG.
As in (b), the lower part of the screen is dark.

FIG. 10B is a time chart showing the ninth embodiment of the present invention in the same manner as FIG. 10A.
The light source is scanned in the order of red, green, and blue as in the eighth embodiment. Note that this order can be arbitrarily exchanged in correspondence with the exchange of data signals. In the present embodiment, the light source does not enter the panel side and switches to another color during the first writing period after resetting and during the period until the display is stabilized, as well as during the resetting period of the scanning line. The difference from the eighth embodiment is that the period is set. That is, after the transition from the reset state to the new display state from the upper part to the lower part of the panel is completed, the light of the light source enters the panel and is recognized by the observer. With this method, the luminance distribution in the panel plane seen in the eighth embodiment is eliminated, and uniform luminance is obtained over the entire screen. FIG. 18 is a time chart showing the configuration and operation of the time distribution of the luminance of the light source and the time distribution of each scanning line in a mode for eliminating the luminance distribution in the panel surface in the conventional field sequential display. Conventionally, the light from the light source is incident on the panel after the reset is completed and the writing display is stabilized, and the time for turning on the light source is extremely short. On the other hand, in the present embodiment, since the light source lighting time can be long, the brightness of the entire panel is high.

FIG. 11 is a time chart showing a tenth embodiment of the present invention, similarly to FIG. 9 (a). The light source is scanned in the order red, green and blue. This order is
It is possible to arbitrarily exchange the data signals in response to the exchange. The scanning is the same as the scanning timing of the bidirectional scanning of the first embodiment in FIG. 1, but since the display is a field sequential display, three reset periods 103 exist in one frame. During each color scan,
Two writing periods 101 are provided, and positive and negative data signals are distributed and applied to each writing period for each code. Each writing period 101 corresponds to bidirectional scanning of scanning from above and scanning from below. In FIG. 11, for example, when the light source is red, scanning from the top is performed, and then, a reset period, scanning from the bottom, a reset period, etc., a set of two writings and two resets is set for each color. It is repeated three times in synchronization. Here, one write and one reset are referred to as a subfield. There is a first subfield and a second subfield for each color, and these sets are repeated three times to form one frame. The light source is turned on at the beginning of the first subfield, turned off immediately before the reset period of the second subfield, and is switched to another color during the reset period. As a result of scanning of these light sources and scanning lines, information of each color is displayed in one frame, and color display can be performed in units of one pixel. Since bidirectional scanning is performed in the same manner as in the first embodiment, it is not necessary to adjust the lighting time of the light source as in the ninth embodiment, and there is no luminance distribution in the panel surface. Further, since the light source lighting period is longer than that of the conventional method shown in FIG. 18, the luminance is high. Further, in FIG. 18, the light source needs to be turned on / off for each subfield, but this is not necessary in the present embodiment.

The eleventh embodiment of the present invention is a liquid crystal display device using any one of the driving methods of the first to seventh embodiments. FIG. 12 is a plan view showing a liquid crystal display device of the present embodiment and showing a TFT (thin film transistor) array on one substrate. The substrate according to the present embodiment is composed of a TFT substrate and a counter substrate. As shown in FIG. 12, the TFT substrate includes an array including a plurality of gate bus lines 3, a plurality of drain bus lines 1, and a plurality of TFTs 1. Having at least one pixel electrode 4 for each pixel
Having. FIG. 13 is a schematic diagram illustrating a cross section of the liquid crystal display device of the present embodiment. An electrode 7 is formed on each of the two support substrates 6, and an alignment film 8 for aligning liquid crystal is formed thereon.
Is formed. A liquid crystal 9 is sandwiched between the pair of support substrates 6, and a pair of polarizing plates 5 is provided outside.

The operation of this embodiment is as follows. A signal data waveform corresponding to each driving method is applied to each drain bus line 1 at a predetermined frequency corresponding to each gate line 3. On the other hand, each gate bus line 3 is applied with the waveform shown in each embodiment such that the TFT 2 is turned on when that line is selected, whereby the waveform of the drain line 1 is applied to the liquid crystal by the display electrode. Is applied to The voltage is held in the liquid crystal unit until the gate line 3 is selected again. Thus, a display holding operation can be performed even if the liquid crystal does not have a memory property. Reset is
A predetermined signal data for reset is applied to the drain line 1 and a waveform for turning on the switch of the TFT 1 is applied at the timing shown in each embodiment. As a result, a liquid crystal display device to which any of the driving methods according to the first to seventh embodiments of the present invention is applied is realized.

The twelfth embodiment of the present invention is a liquid crystal display device having a structure similar to that shown in FIG. 13 and using one of the driving methods of the eighth to tenth embodiments.
An electrode 7 is formed on each of the two support substrates 6, and an alignment film 8 for aligning the liquid crystal 9 is formed thereon. The liquid crystal 9 is sandwiched between the pair of support substrates, and the pair of polarizing plates 5 is provided outside. Further, a light source (not shown) for field sequential display is provided on one of the polarizing plates 5. With this configuration, a liquid crystal display device to which any of the driving methods according to the eighth to tenth embodiments is applied is realized.

According to a thirteenth embodiment of the present invention, in the liquid crystal display devices of the eleventh and twelfth embodiments, the viewing angle dependency of the liquid crystal display mode and the luminance distribution in the panel plane due to the driving method are cancelled, or , Adopt a configuration that alleviates it. According to this configuration, the viewing angle dependency of the liquid crystal display mode and the in-plane luminance distribution due to the driving method are reduced, and a liquid crystal display device with very good display is realized.

Hereinafter, specific examples of the configuration of a liquid crystal display device to which the above-described embodiment of the present invention is actually applied will be described as examples.

First Embodiment: 480 gate bus lines and 640 drain bus lines are made of chromium (Cr) formed by sputtering, the line width is set to 10 μm, and the gate insulating film is made of silicon nitride (Cr). SiNx) was used. The size of one unit pixel is 330 μm in height and 110 μm in width.
A TFT (thin film transistor) was formed using amorphous silicon, and a pixel electrode was formed by sputtering using indium tin oxide (ITO) as a transparent electrode. The glass substrate on which the TFTs are formed in the form of an array is
Substrate. After forming a light-shielding film using chromium on a second substrate facing the first substrate, ITO
Was formed, a color filter was formed in a matrix by a dyeing method, and a protective layer using silica was provided on the upper surface of the transparent electrode. Thereafter, a soluble polyimide was printed by a printing method and baked at 180 ° C. to remove the solvent. A buff cloth using rayon is wound around a roller having a diameter of 50 mm on the polyimide film, the number of rotation of the roller is 600 rpm, and the stage moving speed is 40 mm /.
Rubbing was performed in a direction such that parallel rubbing was performed with a rubbing frequency of 0.7 mm for 2 seconds. The thickness of the alignment film measured by the contact step meter was about 500 Å, and the pretilt angle measured by the crystal rotation method was 7 degrees. On one of such a pair of glass substrates, a micro-pearl, which is a spherical spacer having a diameter of about 9.5 μm, was dispersed, and on the other side, a cylindrical glass rod spacer having a diameter of about 9.5 μm was dispersed. An ultraviolet-curable sealing material was applied. These substrates were placed so that the rubbing directions were parallel to each other, and the substrates were opposed to each other. The sealing material was cured by non-contact irradiation with ultraviolet light to assemble a panel having a gap of 9.5 μm. A nematic liquid crystal was injected into this panel. In the present embodiment, a compensating plate is added so as to be in an OCB (optically compensated birefrigence) display mode shown on pages 927 to 930 of S.I.D.94 Digest. A driving driver was attached to the liquid crystal panel manufactured in this manner to obtain a liquid crystal display device.

The driving method of the first embodiment is applied to the present liquid crystal display device. Specifically, the reset period 103 is set to 5 milliseconds, the writing time of each scanning line is set to 15 microseconds,
One field period was set to 16.7 milliseconds. as a result,
Even in the last scanning line in the scanning order, a display period of about 4.5 milliseconds was secured in one field. By adding both of the bidirectional scanning, a display period of about 16 milliseconds was obtained within one frame. The response speed when the liquid crystal rises is about several milliseconds to 5 milliseconds, depending on the applied voltage, and the response ends after the writing is completed. The liquid crystal display mode has a very wide viewing angle and hardly any viewing angle dependence. When this liquid crystal display device was observed, no luminance distribution was observed in the panel surface due to driving, so that a display with a wide viewing angle utilizing the characteristics of the liquid crystal display mode with a wide viewing angle was obtained.

Second Embodiment A TFT substrate and a color filter substrate were manufactured in the same manner as in the first embodiment. Thereafter, a polyamic acid was applied by spin coating, baked at 200 ° C., and imidized to form a polyimide film. This polyimide film is coated with a buff cloth using nylon having a diameter of 50 mm.
mm roller, the number of rotation of the roller 600r
pm, stage moving speed 40 mm / sec, pushing amount 0.7
Rubbing was performed in such a direction as to give 10 ° cross rubbing with 2 mm rubbing times. The thickness of the alignment film measured by the contact step meter was about 500 angstroms, and the pretilt angle measured by the crystal rotation method was 1.5 degrees. Approximately 2 μm on one of such a pair of glass substrates
A fine-grained spacer (micropearl), which is a spherical spacer having a diameter, was sprayed, and a thermosetting sealing material in which a cylindrical glass rod spacer having a diameter of about 2 μm was dispersed was applied to the other side. These substrates were arranged so that the rubbing directions were cross-rubbed with each other by 10 °, and the sealing material was cured by heat treatment to assemble a panel having a gap of 2 μm. An antiferroelectric liquid crystal composition having a V-shaped switching shown on pages 61 to 64 of Asia Display 95 was injected into this panel in an isotropic phase (Iso) at 85 ° C. in a vacuum. A rectangular wave having a frequency of 3 kHz and an amplitude of ± 10 V is applied to the entire panel using an arbitrary waveform generator and a high-output amplifier at 85 ° C., and a rate of 0.1 ° C./min to room temperature while applying an electric field. And slowly cooled. A driving driver was attached to the liquid crystal panel manufactured in this manner to obtain a liquid crystal display device.

The driving method of the fifth embodiment was applied to the present liquid crystal display device. Specifically, the reset period 103 is 1 millisecond, the writing time of each scanning line is 10 microseconds,
One field period was 16.7 milliseconds, and one frame period was 33.4 milliseconds. As a result, a display period of 10 ms or more was secured in one field even in the last scanning line in the scanning order. Addition of both bidirectional scans results in 1
A display period of 25 ms was obtained within the frame. The response speed at the time of rising of the liquid crystal depends on the applied voltage, but is about several hundred microseconds, and the response ends after the writing is completed. The liquid crystal display mode has a very wide viewing angle and hardly any viewing angle dependence. Observation of this liquid crystal display device revealed that there was no luminance distribution in the panel surface due to driving, and a wide viewing angle display was obtained utilizing the characteristics of the wide viewing angle liquid crystal display mode.

Third Embodiment: The configuration of the liquid crystal panel is the same as that of the second embodiment. A field-sequential liquid crystal display device was formed by using a driving driver and a backlight capable of high-speed switching on the liquid crystal panel.

In the present liquid crystal display device, the driving method and the scanning of the luminance of the light source are according to the tenth embodiment. Specifically, the reset period 103 is 1 millisecond, the writing time of each scanning line is 5 microseconds, and one frame period is 33.4.
Milliseconds. As a result, the display period for each color is
Times of 6.5 milliseconds or more were obtained. Further, there was no luminance distribution in the panel surface.

As a comparative example, the same liquid crystal display mode as that of the third embodiment was used, and a driving method shown in FIG. 18 and a field sequential liquid crystal display device using scanning of the luminance of a light source were used. As in the third embodiment, there was no luminance distribution in the panel surface, but the display period for each color was about 4 milliseconds, and the panel luminance was about half that of this embodiment.

Fourth Embodiment A microdisplay was manufactured as a reflection type projector. The micro-display was manufactured in the same manner as a display display microdisplay as shown in the beginning of the January 1997 issue of Advanced Imaging. Specifically, an MO is placed on a silicon wafer.
A DRAM was manufactured by forming an S-FET according to the 0.8 μm rule. The size and the like were a die size of １ ／ inch, and a pixel pitch of about 10 μm formed a 1-mega DRAM. The aperture ratio of the pixel was 90% or more. Furthermore,
The surface of the formed DRAM was flattened by applying a chemical mechanical polishing technique. On the other hand, a cover glass for microscopic observation was used for the facing substrate.
A portion including a drive circuit was cut out from the silicon wafer, an alignment film was printed with a soluble polyimide, and baked at 170 ° C. to remove the solvent. This polyimide film was wrapped with a nylon buff cloth wound around a roller having a diameter of 50 mm, rubbed at a roller rotation speed of 600 rpm, a stage moving speed of 40 mm / sec, a pushing amount of 0.7 mm, and rubbing twice. The thickness of the alignment film measured by the contact step meter was about 500 angstroms, and the pretilt angle measured by the crystal rotation method was 1.5 degrees. In addition, a photocurable sealing material in which a cylindrical glass rod spacer having a diameter of about 2 μm was dispersed was applied. These substrates were arranged to face each other, and the sealing material was cured by non-contact UV treatment to assemble a panel having a gap of 2 μm. On this panel, 61 of Asia Display 95
The antiferroelectric liquid crystal composition having a V-shaped switching shown from page to page 64 was injected in an isotropic phase (Iso) at 85 ° C. in a vacuum. With the temperature maintained at 85 ° C, the frequency is 3
A rectangular wave having an amplitude of ± 10 V at kHz was applied, and while applying an electric field, the sample was gradually cooled to room temperature at a rate of 0.1 ° C./min.
Further, a reflection type field sequential projector was manufactured using a light emitting diode of three colors, a collimating lens for obtaining parallel light, a polarization conversion element, and a projection lens.

The method of driving the liquid crystal display device is based on the method of the ninth embodiment. As a result, good display without in-plane luminance distribution was obtained.

Fifth Embodiment: A TFT substrate and a color filter substrate were manufactured in the same manner as in the first embodiment. Thereafter, a soluble polyimide was printed by a printing method and baked at 180 ° C. to remove the solvent. A buff cloth using rayon is wound around a roller having a diameter of 50 mm on the polyimide film, and the rotation speed of the roller is 600 rpm, the stage moving speed is 40 mm / sec, the pushing amount is 0.7 mm, and the rubbing is performed twice so that the rubbing is performed at 90 degrees. Rubbed in different directions. The thickness of the alignment film measured by the contact step meter was about 500 Å, and the pretilt angle measured by the crystal rotation method was 3 degrees. One of such a pair of glass substrates is sprinkled with micro-pearls, which are spherical spacers having a diameter of about 5.5 μm, and about 5.5 μm on the other side.
An ultraviolet-curable sealing material in which a cylindrical glass rod spacer having a diameter was dispersed was applied. These substrates were arranged so that the rubbing directions were rubbed at 90 degrees to each other, and the sealing material was cured by non-contact UV irradiation to assemble a panel having a gap of 5.5 μm. A nematic liquid crystal was injected into this panel.
In this embodiment, the TN type liquid crystal display mode is configured. A driving driver was attached to the liquid crystal panel manufactured in this manner to obtain a liquid crystal display device.

The driving method of this embodiment is the same as the conventional driving method shown in FIG. However, the direction of the viewing angle dependence in the vertical direction of the TN display mode was adjusted so that the display became brighter when viewed from above and darkened when viewed from below. As a result, when observing the panel from the front, the luminance distribution in the panel surface and the viewing angle dependency due to the driving method compensated each other, and a better display than the conventional panel was obtained.

Although the present invention has been described based on the preferred embodiments, the liquid crystal driving method and the liquid crystal display device of the present invention are not limited to the above embodiments and examples. Various modifications and changes made to the configurations of the above-described embodiment and examples are also included in the scope of the present invention.

[0063]

According to the present invention, in a high-speed response liquid crystal display device, even when a reset pulse is used, the in-plane luminance distribution is small, the flicker is small, the contrast is high, the luminance is high, and the electrical asymmetry is reduced. A driving method without any influence can be realized. Further, according to the present invention, a liquid crystal display device and a field sequential liquid crystal display device using those driving methods can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing the configuration and operation of a first embodiment of the present invention, wherein (a) is a time chart for each scanning line,
(B) is a waveform diagram of the scanning line voltage and transmittance of the first scanning line, and (c) is a waveform diagram of the scanning line voltage and transmittance of the eighth scanning line.

FIGS. 2A and 2B are luminance distribution diagrams in a panel surface showing an operation of the first embodiment example, where FIG. 2A is a luminance distribution at each moment from 1A to 1F in FIG. 1A, and FIG. This is a luminance distribution averaged over time.

FIG. 3 is a diagram showing a configuration and operation of a second embodiment of the present invention, wherein (a) is a time chart for each scanning line,
(B) is a waveform diagram of the scanning line voltage and transmittance of the first scanning line, and (c) is a waveform diagram of the scanning line voltage and transmittance of the eighth scanning line.

4A and 4B are luminance distribution diagrams in a panel showing the operation of the second embodiment of the present invention. FIG. 4A is a luminance distribution at each moment from 2A to 2F in FIG. 3A, and FIG. This is a luminance distribution averaged over a frame time.

5A and 5B are diagrams showing a configuration and an operation of a third embodiment of the present invention, wherein FIG. 5A is a time chart for each scanning line, and FIG.
Is a waveform diagram of the scanning line voltage and transmittance of the first scanning line,
(C) is a waveform diagram of the scanning line voltage and transmittance of the eighth scanning line.

FIG. 6 is a diagram showing a configuration and operation of a fourth embodiment of the present invention, wherein (a) is a time chart for each scanning line,
(B) is a waveform diagram of the scanning line voltage and transmittance of the first scanning line, and (c) is a waveform diagram of the scanning line voltage and transmittance of the eighth scanning line.

FIGS. 7A and 7B are diagrams showing the configuration and operation of a fifth embodiment of the present invention, wherein FIG. 7A is a time chart for each scanning line,
(B) is a waveform diagram of the scanning line voltage and transmittance of the first scanning line, and (c) is a waveform diagram of the scanning line voltage and transmittance of the eighth scanning line.

FIGS. 8A and 8B are diagrams showing the luminance distribution in the panel surface averaged over the frame time, showing the operation of the third to fifth embodiments of the present invention, wherein FIG. 8A shows the third embodiment and FIG. () Is a distribution diagram of the fourth and fifth embodiments.

FIGS. 9A and 9B are diagrams showing the configuration and operation of the sixth and seventh embodiments of the present invention, wherein FIG. 9A is a time chart for each scanning line of the sixth embodiment, and FIG. FIG. 9C is a time chart for each scanning line in the seventh embodiment of the present invention, which is a time-averaged in-plane luminance distribution diagram.

FIGS. 10A and 10B are diagrams showing the configuration and operation of the eighth and ninth embodiments of the present invention, wherein FIG. 10A is a light source luminance and time chart for each scanning line of the eighth embodiment, and FIG. 21 is a time chart for each light source luminance and scanning line in the ninth embodiment.

FIG. 11 is a diagram showing the configuration and operation of a tenth embodiment of the present invention, and is a time chart for each light source luminance and scanning line.

FIG. 12 is a plan view of a thin film transistor array of a liquid crystal display according to an eleventh embodiment of the present invention.

FIG. 13 is a side view of a liquid crystal display device according to an eleventh embodiment.

14A and 14B are diagrams showing a conventional driving method, wherein FIG. 14A is a time chart for each scanning line, FIG. 14B is a waveform diagram of the scanning line voltage and transmittance of the first scanning line, and FIG. It is a waveform diagram of the scanning line voltage and transmittance | permeability of the 8th scanning line.

15A and 15B are luminance distribution diagrams in a panel surface according to a conventional driving method, where FIG. 15A is a luminance distribution at each instant from 1A to 1F in FIG. 14A, and FIG. 15B is a luminance averaged over a frame time. Distribution.

16A and 16B are diagrams for explaining a step response in a high-speed response liquid crystal. FIG. 16A is a waveform diagram of an applied voltage, and FIG. 16B is a change in transmittance at the time of the applied voltage in FIG.

17A and 17B are diagrams illustrating a data signal waveform for preventing a step response, where FIG. 17A is a waveform diagram of an applied voltage, and FIG.
(A) is a change in transmittance when the applied voltage is (a).

FIG. 18 is a diagram showing a driving method for eliminating a luminance distribution in a panel surface by a conventional driving method of a field sequential liquid crystal display device, and a configuration of light source luminance, and is a time chart for each light source luminance and scanning line. .

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 drain bus line 2 TFT (thin film transistor) 3 gate bus line 4 pixel electrode 5 polarizing plate 6 substrate 7 electrode 8 alignment film 9 liquid crystal 101 writing period 102 display period 103 reset period

Claims (9)

[Claims] 1. A method for driving a liquid crystal display device, in which a screen is displayed by sequentially scanning scanning lines for each field and a scanning line is subsequently reset, the scanning lines are sequentially scanned in a first field and then all at once. A method for driving a liquid crystal display device, comprising: resetting, scanning in a second field subsequent to the first field in a reverse order to the scanning order in the first field, and then resetting all at once. 2. The method of driving a liquid crystal display device according to claim 1, wherein interlace driving is performed in which the first field and the second field constitute one frame. 3. The driving method of a liquid crystal display device according to claim 2, wherein one scanning line has two writing periods in one frame. 4. The driving method of a liquid crystal display device according to claim 3, wherein one scanning line has two reset periods in one frame. 5. One frame has one reset period in one scanning line, and the absolute value of the data signal voltage at the first write after reset is the data signal voltage at the second write. 4. The method according to claim 3, wherein the absolute value of
3. The method for driving a liquid crystal display device according to 1. 6. A method for driving a field sequential liquid crystal display device in which information of three colors is sequentially displayed in one frame, wherein each display color is driven by the method according to claim 5. For driving a liquid crystal display device. 7. A method for driving a field sequential liquid crystal display device in which information of three colors is sequentially displayed in one frame, wherein each display color is driven by the method according to claim 1. For driving a liquid crystal display device. 8. A liquid crystal display device comprising a liquid crystal driven by the driving method according to claim 1. 9. A liquid crystal display device comprising a liquid crystal driven by the driving method according to claim 6.