JP2000235362A - Liquid crystal display device and its drive method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve a shortage of a charging time at a polarity inversion time and to realize a wide view angle with a ferroelectric liquid crystal and an anti-ferroelectric liquid crystal by successively selecting plural scanning lines answering first and second display areas with a first pitch and a second pitch respectively different from each other. SOLUTION: A whole picture is bisected to an upper part area consisting of (n) pieces of scanning lines and a lower part area consisting of (m) pieces of scanning lines. In respective bisected areas, the order selecting the scanning lines is made different. For instance, in the upper part area, a jumping scan that the picture is updated in the ratio of one piece to three pieces is performed, and in the lower part area, the jumping scan that the picture is updated in the ratio of one piece to two pieces is performed. A whole pixels are updated with three pictures in the upper part area, and are updated with two pictures in the lower part area. In such a manner, by quickening the rewrite of the whole picture with the jumping scan even when deviation is caused in the upper/lower lines, picture quality of an animation, etc., is more improved compared with the case that one frame is completed while sufficiently changing every one line and prolonging the updating time of a picture by providing a region where such a jumping scan is performed that the interval of scanning lines is widened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film transistor (hereinafter referred to as a TF)
Called T. ), A liquid crystal display device having a liquid crystal material sandwiched between an array substrate and a counter substrate, and a method for driving the liquid crystal display device.

[0002]

2. Description of the Related Art An active matrix type liquid crystal display device having a TFT as a driving element for each pixel can provide a high-contrast display without a crosstalk between adjacent pixels, can perform a transmissive display, and is large in size. It is widely used in recent years because it has advantages such as easy conversion.

FIG. 32 is a view for explaining a method of driving a TFT liquid crystal panel using a conventional twisted nematic liquid crystal.

A liquid crystal panel has signal lines and scanning lines arranged in a matrix.
The FT is connected to the transparent pixel electrode. A counter electrode is provided on a counter substrate facing the array substrate provided with the TFTs and the pixel electrodes, and a liquid crystal is interposed between the pixel electrodes and the counter electrodes. FIG. 32 shows k parallel scanning lines arranged along the horizontal direction of the liquid crystal panel.

FIG. 33 is a diagram for explaining the driving order of the scanning lines and the polarity of the signal applied to the pixel electrode through the signal line and the TFT. FIG. 33 (a)
Is a diagram corresponding to the first image, and FIG. 33B is a diagram corresponding to the second image.

Referring to FIGS. 32 and 33 (a), at time t
From 0, scanning lines are sequentially selected one by one from the top to the bottom of the screen. That is, at times t0 to t1, the first to k-th scanning lines are sequentially selected one by one.
This selection is switched for one horizontal scanning period (hereinafter referred to as 1H).
Is performed in a cycle of

In response to the selection of each scanning line, a signal of a negative polarity is given to the signal line, and the signal held by the pixel electrode which has been a positive polarity until then is rewritten to a signal of a negative polarity.

Referring to FIG. 33 (b), when updating of one screen is completed at time t1, scanning lines are sequentially selected again from the top to the bottom of the screen. That is, at time t1
From to t2, the first to k-th scanning lines are sequentially selected one by one. At this time, a positive signal is given to the signal line, and a positive signal is written to the pixel electrode accordingly. At this time, the polarity of the signal held by the pixel electrode is inverted from negative polarity to positive polarity.

The reason for inverting the polarity of the signal applied to each image in this manner is to prevent deterioration of the characteristics of the liquid crystal. The liquid crystal sandwiched between the pixel electrode and the counter electrode is
If a DC voltage is continuously applied between the electrodes, the characteristics deteriorate. Therefore, it is necessary to change the polarity of the signal applied to the liquid crystal at appropriate intervals.

In general, in a liquid crystal panel using a twisted nematic liquid crystal, when rewriting a signal held by each pixel portion, the polarity of the signal is also inverted as shown in FIGS. 33 (a) and 33 (b). The method of making it do is adopted.
The optical characteristics of the liquid crystal used in such a method depend on the absolute value of the voltage applied between the electrodes, and do not depend on the polarity of the voltage.

By the way, in a liquid crystal display device, the number of pixels in the horizontal direction is 640 and the number of pixels in the vertical direction is 480, and a standard for updating an image at a cycle of 60 Hz has become widespread. In this standard, the number of pixels in the vertical direction corresponds to the number of scanning lines. That is, there are 480 scanning lines on the liquid crystal panel. Then, one horizontal scanning period (1H) is set to 30 to 31 μs obtained by subtracting the adjustment margin from 1 ろ 60 ÷ 480 = 34 μs.

In recent years, in such a TFT liquid crystal display device, in order to obtain a wide viewing angle, a ferroelectric liquid crystal having spontaneous polarization or an antiferroelectric liquid crystal is used as a liquid crystal material instead of the twisted nematic liquid crystal. Things are being considered. These ferroelectric liquid crystals and antiferroelectric liquid crystals are
, The time required for charging the capacitor corresponding to the pixel portion sandwiching the liquid crystal between the electrode plates becomes longer because the capacitances are large. Since the charging time generally exceeds 50 μs, it is known that the charging becomes insufficient, and the holding voltage of the capacitor corresponding to the pixel decreases.

The decrease in the holding voltage causes a decrease in the contrast ratio and adversely affects the image quality. Insufficient charging
This can be compensated for by increasing the voltage applied between the electrodes, but increasing the applied voltage requires the use of a driver or array with a high withstand voltage required for driving the liquid crystal pixel electrodes.
This raises the problem of increased costs.

In addition, since the power consumption is increased, especially in a liquid crystal display device which is required to be small and light and has low power consumption such as a portable device, the usable time of the battery is shortened and the operability is reduced. Is also inferior.

In particular, there is a problem that the charging time becomes long when a signal is written to the liquid crystal panel by changing the polarity in order to prevent the deterioration of the liquid crystal. Therefore, in general twisted
There is a problem in applying the method adopted for nematic liquid crystal, that is, the method of inverting the polarity of the signal each time the signal held in each pixel electrode is rewritten, to ferroelectric liquid crystal and antiferroelectric liquid crystal. is there.

In order to solve this problem, only the polarity of a signal to be written to a pixel electrode of a portion corresponding to a part of scanning lines in the entire screen area is inverted, and a pixel of a portion corresponding to other scanning lines is inverted. A pseudo DC drive method has been proposed in which a voltage having the same polarity as that of the previous image display during scanning is applied to the electrodes (H. Okumura et al; "A 15-in. XGA TFT-AFLCDwi
th Quasi-dc Driving Scheme for Monitor Application
s ", SID 98 DIGEST, pp1171-1174 (1998)).

According to this driving method, the time required to reach the predetermined value is shorter in the pixel portion charging the same polarity than in the pixel portion charging the opposite polarity. Most pixel units can be charged to a predetermined value in a short time.

FIG. 34 is a diagram for explaining an example of a pseudo DC drive system. FIG. 34 (a) is a diagram corresponding to the first image, FIG. 34 (b) is a diagram corresponding to the second image, FIG. 34 (c) is a diagram corresponding to the third image, and FIG.
FIG. 4D is a diagram corresponding to the fourth image.

Referring to FIG. 34 (a), before time t0, a pixel signal corresponding to the first to fourth scanning lines holds a positive polarity signal, and the fifth to k-th signals are held. It is assumed that a negative polarity signal is held in a pixel portion corresponding to a scanning line.

At times t0 to t1, the first to k-th scanning lines are sequentially selected one by one, and the first image is updated. First
Positive signals are written to pixel portions corresponding to the fifth to fifth scanning lines, and negative signals are written to pixel portions corresponding to the sixth to k-th scanning lines.

Therefore, at times t0 to t1,
The polarity of the signal held by the pixel portion corresponding to the fifth scanning line is inverted from negative polarity to positive polarity.

Referring to FIG. 34B, in displaying the second image, a positive signal is written to the pixel portions corresponding to the first to sixth scanning lines, and the seventh to k-th pixels are displayed. A negative signal is written to a pixel portion corresponding to the scanning line.

Therefore, between times t1 and t2,
The polarity of the signal held by the pixel portion corresponding to the sixth scanning line is inverted from negative polarity to positive polarity.

Referring to FIG. 34 (c), at the time of displaying the third image, a signal of positive polarity is written in the pixel portions corresponding to the first to seventh scanning lines, and the eighth to k-th pixels are displayed. The signal of the negative polarity is written in the pixel portion corresponding to the scanning line.

Therefore, between times t2 and t3,
The polarity of the signal held by the pixel portion corresponding to the seventh scanning line is inverted from negative polarity to positive polarity.

Referring to FIG. 34D, at the time of displaying the fourth image, a signal of positive polarity is written into the pixel portions corresponding to the first to eighth scanning lines, and the ninth to k-th pixels are displayed. The signal of the negative polarity is written in the pixel portion corresponding to the scanning line.

Therefore, between times t3 and t4,
The polarity of the signal held by the pixel portion corresponding to the eighth scanning line is inverted from negative polarity to positive polarity.

That is, the pseudo DC driving method is a method in which only the polarity of a signal held by a pixel portion corresponding to a part of the whole scanning lines is inverted, and the pixel portions on the other scanning lines are This is a method in which a signal having the same polarity as that in the previous scanning is applied.
In the examples shown in FIGS. 34 (a) to 34 (d), every time one screen is updated, the scanning lines corresponding to the pixel portions whose polarity is changed are shifted one by one, and the screen is updated k times. The polarity of the signal held by all the pixel portions of the liquid crystal panel is inverted.

Next, a simple flow of the pseudo DC driving method will be described. FIG. 35 is a flowchart showing the operation of the conventional pseudo DC driving method.

Referring to FIG. 35, first, at step S100
Is set to an initial value. That is, the polarity p of the signal is positive, the display line number i is set to 1, and the number j of the line whose polarity is inverted is also set to 1. In this specification, a line indicates a pixel portion corresponding to each scanning line.

Next, in step S101, display of an image is started. In step S102, it is determined whether or not the line number i to be displayed is equal to or less than the line number j whose polarity is inverted at the time of displaying the image.

The display line number i is the polarity inversion line number j
If smaller or equal, the process proceeds to step S103, where an image signal is applied to the display line with the polarity p. On the other hand, if the display line number is larger than the line number whose polarity is to be inverted, the process proceeds to step S104, and an image signal is given to the display line with the inverted polarity of the polarity p.

Next, the process proceeds to step S105, where the display line number i is incremented. And step S1
Proceeding to 06, it is determined whether or not the number of display lines exceeds the total number of lines k of the image.

If the number i of display lines does not exceed the number k of all lines, the flow advances to step S111 to display the next line.

If the number of display lines exceeds the number k of all lines of the image, the display of one image has been completed, and the flow advances to step S107. When the display of one image is completed, the display line number is returned to 1 in step S107.
Then, in step S108, the line number for which the polarity is inverted in the next image is incremented, and step S1 is performed.
Go to 09.

In step 109, it is determined whether or not the display reversed line number j exceeds the total number k of lines.

If the number j of the display inversion lines exceeds the total number of lines k, it indicates that the polarity inversion of the signal of the entire screen has been completed, and the flow advances to step S110. In step S110, the line whose polarity is to be inverted next is returned to the first line, and the polarity of the applied signal is inverted. And
Proceed to step S112.

If the polarity inversion line j does not exceed the total number k of lines in step S109, the polarity inversion of the signal of the entire screen has not been completed, so that step S1 is executed.
Proceed to 12 to move to the next image display.

In step S112, a process for shifting to the next image display is performed, and the process returns to step S101 to start displaying a new image.

[0040]

However, the pseudo D
In the C drive method, although the deterioration of the liquid crystal can be prevented, the charging time is insufficient for the pixel portion on the scanning line whose polarity has been inverted, so that there is a problem that a luminance difference occurs with the surrounding pixel portion.

It is an object of the present invention to provide a liquid crystal display device having a wide viewing angle using a ferroelectric liquid crystal or an antiferroelectric liquid crystal, which eliminates a shortage of charging time at the time of polarity reversal.

When the number of pixels increases, the selection time of the scanning line decreases in inverse proportion to the number of pixels. Therefore, even in a conventional display device using a twisted nematic liquid crystal, the charging time of each pixel portion is insufficient. There was a problem that would be.

Another object of the present invention is to provide a liquid crystal display device in which the shortage of charging time when the number of pixels is increased is eliminated even in a display device using twisted nematic liquid crystal.

[0044]

According to a first aspect of the present invention, there is provided a liquid crystal display device comprising: a liquid crystal material; a pair of substrates sandwiching the liquid crystal material; and at least one of the pair of substrates. A plurality of pixel electrodes provided in a matrix corresponding to the provided counter electrode and the pixels of the liquid crystal display device, and controlling the state of a portion corresponding to the pixel of the liquid crystal material by a potential difference applied to the counter electrode; And a plurality of scanning lines for selecting each row of pixel electrodes arranged along the horizontal direction of the screen, and a plurality of scanning lines arranged so as to intersect with the plurality of scanning lines, and a potential difference between the pixel electrode and the counter electrode. A plurality of signal lines transmitting an update signal for updating a signal held as, and provided at the intersections of the plurality of scan lines and the plurality of signal lines, respectively, and activated by the scan lines to update the update signal. For pixel electrode A plurality of switching elements is reached,
A screen drive unit for selecting a scan line and supplying an update signal to the plurality of signal lines, the screen drive unit sequentially selecting a plurality of scan lines corresponding to a first display area on the screen at a first pitch. A plurality of scanning lines corresponding to a second display area on the screen are sequentially selected at a second pitch different from the first pitch.

According to a second aspect of the present invention, in the liquid crystal display of the first aspect, the first pitch is equal to n scanning lines (n is a natural number of 2 or more). 2
Is m scanning lines (m is a natural number smaller than n).

According to a third aspect of the present invention, in the liquid crystal display device according to the second aspect, the second pitch is equal to one scanning line.

According to a fourth aspect of the present invention, in the liquid crystal display device according to the second aspect, the second pitch is equal to or more than two scanning lines.

According to a fifth aspect of the present invention, in the configuration of the liquid crystal display device of the second aspect, the screen driving section includes a plurality of scanning lines in the first display area for each first line. And a plurality of scanning lines in the second display area are selected in a second selection time shorter than the first selection time per line.

According to a sixth aspect of the present invention, in the liquid crystal display device according to the fifth aspect, the screen drive unit selects a plurality of scanning lines in the first display area when selecting a plurality of scanning lines.
An update signal having a polarity opposite to that of the update signal given at the time of displaying the previous image is given to a plurality of signal lines.

According to the liquid crystal display device of the present invention, in addition to the configuration of the liquid crystal display device of the fifth aspect, the screen driving unit may generate an update signal based on a synchronization signal and a clock signal corresponding to a display image. A display control circuit for outputting a polarity inversion signal for controlling polarity and a selection control signal for controlling selection of a scanning line; and a polarity for receiving an image input signal corresponding to a display image and inverting the polarity in accordance with the polarity inversion signal An inverting circuit,
A signal line driving circuit which receives and holds the output of the polarity inversion circuit and supplies an update signal to the plurality of signal lines.

In the liquid crystal display device according to the eighth aspect, in the liquid crystal display device according to the first aspect, the liquid crystal display device displays a first image group and a second image group on a screen in a predetermined order. The first image group includes at least the first display image, and when the first display image is displayed, the number of scanning lines corresponding to the first pitch is n, and (n Is 2
When the number of scanning lines corresponding to the second pitch is m (m is a natural number smaller than n), the number of scanning lines corresponding to the first pitch is m. And at least a second display image in which the number of scanning lines corresponding to the second pitch is displayed as n.

According to a ninth aspect of the present invention, in the liquid crystal display device according to any one of the first to eighth aspects, the liquid crystal material is a ferroelectric liquid crystal.

According to a tenth aspect of the present invention, in the liquid crystal display device according to any one of the first to eighth aspects, the liquid crystal material is an antiferroelectric liquid crystal.

According to an eleventh aspect of the present invention, in the liquid crystal display device according to any one of the first to eighth aspects, the liquid crystal material is a twisted nematic liquid crystal.

A driving method for a liquid crystal display device according to a twelfth aspect is a driving method for a liquid crystal display device, wherein a liquid crystal material,
A pair of substrates sandwiching a liquid crystal material, a counter electrode provided on at least one of the pair of substrates, and a matrix provided corresponding to pixels of the liquid crystal display device, respectively, are provided by a potential difference given to the counter electrode. A plurality of pixel electrodes for controlling the state of a portion corresponding to the pixel of the liquid crystal material; a plurality of scanning lines for selecting a row of pixel electrodes arranged along the horizontal direction of the screen; A plurality of signal lines that are arranged crossing the scanning lines and transmit an update signal for updating a signal held as a potential difference between the pixel electrode and the counter electrode; a plurality of scanning lines and a plurality of signal lines; And a plurality of switching elements that are provided corresponding to the intersections of the scan lines and that are activated by the scanning lines and transmit the update signal to the pixel electrodes. Sequentially selecting a plurality of scanning lines corresponding to the area at a first pitch and displaying an image in a first display area; and selecting a plurality of scanning lines corresponding to a second display area on the screen at a first pitch And sequentially displaying the images in the second display area at a second pitch different from the second pitch.

In the driving method for a liquid crystal display device according to the thirteenth aspect, in the configuration of the driving method for a liquid crystal display device according to the twelfth aspect, the first pitch is equal to n scanning lines (n
Is a natural number of 2 or more), and the second pitch is m scanning lines (m is a natural number smaller than n).

According to a fourteenth aspect of the present invention, in the driving method of the liquid crystal display device according to the thirteenth aspect, the second pitch is equal to one scanning line.

In the driving method of a liquid crystal display device according to the fifteenth aspect, in the configuration of the driving method of the liquid crystal display device according to the thirteenth aspect, the second pitch is equal to or more than two scanning lines.

According to a sixteenth aspect of the present invention, in the driving method of the liquid crystal display device according to the thirteenth aspect, the step of displaying an image in the first display area comprises the first display step. The step of selecting a plurality of scanning lines in the region at a first selection time per one line, and the step of displaying an image in the second display region includes the step of selecting the plurality of scanning lines in the second display region. The method includes a step of selecting a line with a second selection time shorter than the first selection time.

According to a seventeenth aspect of the present invention, in the driving method of the liquid crystal display device according to the sixteenth aspect, the step of displaying an image in the first display area includes the step of: When selecting multiple scan lines in the area,
The method further includes the step of applying to the plurality of signal lines an update signal having a polarity opposite to that of the update signal given when the previous image is displayed.

In the driving method of a liquid crystal display device according to the present invention, the liquid crystal display device may further include a first image group and a second image on a screen. The first image group is repeatedly displayed in a predetermined order, and in the first image group, when the first display image is displayed, the number of scanning lines corresponding to the first pitch is n, and (n is 2 or more) , The number of scanning lines corresponding to the second pitch is m (m is a natural number smaller than n), and the number of scanning lines corresponding to the first pitch is m in the second image group. And the second
The number of scanning lines corresponding to the pitch of n is indicated by n
At least.

According to a nineteenth aspect of the present invention, in the driving method of the liquid crystal display device according to any one of the twelfth to eighteenth aspects, the liquid crystal material is a ferroelectric liquid crystal.

According to a twentieth aspect of the present invention, in the driving method of the liquid crystal display device according to any one of the twelfth to eighteenth aspects, the liquid crystal material is an antiferroelectric liquid crystal.

According to a twenty-first aspect of the present invention, in the method of driving a liquid crystal display device according to any one of the twelfth to eighteenth aspects, the liquid crystal material is a twisted nematic liquid crystal.

[0065]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

[First Embodiment] FIG. 1 is a diagram showing a configuration of a liquid crystal display device 1 of the present invention.

Referring to FIG. 1, a liquid crystal device 1 includes a liquid crystal panel 2 and a screen drive control unit 8 for performing control for displaying an image on liquid crystal panel 2.

The liquid crystal display device 1 further includes a light source 4 for irradiating the liquid crystal panel 2 with light from the rear of the liquid crystal panel, and a light source driving unit 6 for driving the light source 4.

The liquid crystal panel 2 is composed of two transparent substrates such as glass, and liquid crystal is sealed between them.
A transparent pixel electrode and a switching element for turning on and off the pixel electrode are formed on one glass substrate (array substrate), and a transparent counter electrode is formed on another glass substrate (counter substrate). The liquid crystal is interposed between the electrodes. Then, a voltage is applied between the electrodes corresponding to each pixel. However, the counter electrode may be provided on the array substrate adjacent to the pixel electrode.

FIG. 2 is a block diagram showing a schematic configuration of the liquid crystal panel 2 and the display control unit 8 in FIG.

Referring to FIG. 2, this liquid crystal display device has an inverting circuit 10 receiving video signal VIN and inverting or inverting the polarity in accordance with control signal PINV to output signal VIN2.
And a clock signal CLOCK and a horizontal synchronization signal HSYNC.
And a control signal PIN receiving the vertical synchronization signal VSYNC.
A display control circuit 12 for outputting V and S1, and a signal VIN2
And an X driver 14 receiving a control signal S1 and a Y driver 20 controlled by the display control circuit 12.

This liquid crystal display further includes a display panel 22 in which signal lines are driven by an X driver and scanning lines are driven by a Y driver.

The X driver controls the control signal S1 output from the display control circuit 12 based on the clock signal and the synchronization signal.
And a shift register 16 that sequentially shifts the received signals and a signal V corresponding to each signal line based on the output of the shift register.
And a sample and hold circuit 18 for taking in and holding IN2.

In FIG. 2, for the sake of simplicity, the display panel section includes scanning lines L1 to L16 and signal lines D1 to D2.
A configuration including a 16 × 20 pixel section controlled by 0 is shown as an example.

FIG. 3 is an equivalent circuit diagram showing an enlarged part of the display panel 22 in FIG.

Referring to FIG. 3, scanning lines L1 arranged in parallel in one direction are provided on an array substrate of display panel section 22.
There are provided signal lines D1 to D3 which provide a signal corresponding to image data to the pixel portion orthogonally to L5. A pixel portion 32 is provided at the intersection of these scanning lines and signal lines.

Each pixel section has a pixel electrode 44,
And a counter electrode 46 provided on the counter substrate. Liquid crystal is interposed between the pixel electrode 44 and the counter electrode 46, and the capacitor 36 is formed.

The pixel section 32 further includes a switching element provided corresponding to an intersection with each scanning line. FIG.
Here, an example including a TFT 34 as a switching element is shown.

The gate electrode 42 of the TFT 34 is connected to the corresponding scanning line, the drain electrode 38 of the TFT 34 is connected to the corresponding signal line, and the source electrode 40 of the TFT is connected to the pixel electrode 44. A storage capacitor may be provided in parallel with the capacitor 36 to increase the signal holding time of the capacitor 36, but this is not shown here.

The operation will be briefly described with reference to FIGS. 2 and 3. The scanning lines L 1 to L 16 are sequentially selected one by one by the Y driver 20. From the sample and hold circuit 18 included in the X driver 14 in synchronization with the selection of the scanning line, a signal is supplied to the pixel portion corresponding to each scanning line via the signal lines D1 to D20. Those signals are held in each capacitor 36. Thus, each pixel is updated and the screen is updated.

The configuration described above with reference to FIGS. 1 to 3 is similarly used in Embodiments 2 to 6 described later.

FIG. 4 is a diagram for explaining the manner in which a scanning line is selected on the screen according to the first embodiment.

FIG. 5 is a diagram for explaining the order in which scanning lines are selected in the first embodiment.

Referring to FIGS. 4 and 5, in the first embodiment, the entire screen is divided into an upper area of a screen composed of n scanning lines and a lower area of a screen composed of m scanning lines.
In each of the divided areas, the order of selecting the scanning lines is different. As an example, in FIG. 4, an interlaced scan in which the screen is updated at a rate of one out of three is performed in the upper region. In the lower region, interlaced scanning is performed in which the screen is updated at a ratio of one for every two lines. Note that scanning lines indicated by broken lines in FIG. 4 indicate scanning lines corresponding to pixels that are not updated during screen updating, and solid lines indicate scanning lines corresponding to pixels to be updated.

Here, in order to facilitate comparison between FIG. 4 and FIG. 5, it is assumed that the total number of scanning lines is the same and k = n + m.

First, in the first image, as shown in FIG. 5A, the upper region of FIG. 4 has the first, fourth, seventh, tenth,. The scanning lines are sequentially selected one by one. That is, in the upper region of the screen, the scanning lines selected at a pitch of three scanning lines move. Subsequently, in the lower region, the scanning lines are separated by (n + 1) th, (n + 3), (n + 5), and (n) at intervals of one scanning line.
+7)... Are sequentially selected one by one. That is, in the lower area of the screen, the scanning lines selected at the pitch of two scanning lines move.

In the next image, as shown in FIG.
In the screen area of n scanning lines at the top of the screen, the scanning lines are selected one by one in the order of the second, fifth, eighth, eleventh,. In other words, in the upper area of the screen, the scanning line at which scanning is started is a scanning line one line below the previous image (second scanning line), and thereafter, at a pitch of three scanning lines similarly to the previous image. The selected scan line moves. Subsequently, in the lower region, the (n + 2) th, (n + 4), (n + 6), and (n +
8) The scanning lines are sequentially selected one by one in the order of. In other words, in the upper area of the screen, the scanning line at which scanning is started is one scanning line below the previous image (the (n + 2) th scanning line), and thereafter, as in the previous image, two scanning lines are provided. The scanning line selected by the pitch moves.

In the next image, as shown in FIG. 5C, the third, sixth, ninth, twelfth,.
Are sequentially selected one by one in the order of (n). Subsequently, in the screen area of m scanning lines at the bottom of the screen, the (n)
+1), (n + 3), (n + 5)... One scanning line at a time. Thereafter, in the order shown in FIGS. 5A to 5C, all pixels are updated with three images in the upper region of the screen and two images in the lower region of the screen.

As described above, the image quality of a moving image can be improved by providing a region for performing interlaced scanning with a wide scanning line interval. This is because the time required to scan an entire screen is k · H in the past,
In the first embodiment, the time required to scan the entire screen is (n / 3 + m / 2) · H, and since k = n + m, it is only (n · 2/3 + m / 2) · H. This is because the scanning time can be shortened. This is particularly effective when the number of scanning lines is large.

However, the screen portion scanned at intervals is
Discontinuous points occur with pixels on the upper and lower scanning lines.

However, generally, human eyes have a low resolution (resolution) for moving objects. Therefore, the entire image can be rewritten faster by interlaced scanning even if a shift occurs between the upper and lower lines, as compared with the case where the charging is sufficiently performed for each line and the screen updating time is extended to complete one frame. If it is a video, it looks more natural.

Further, in general, a screen has a strong correlation between adjacent pixels, and substantially no influence is obtained since most of the screen is substantially a continuous portion other than the outline portion.

Therefore, in the first embodiment, the updating speed of the screen is increased, and it is possible to make the moving image look more natural.

[Second Embodiment] FIG. 6 is a diagram for explaining a manner of selecting a scanning line on a screen according to a second embodiment.

FIG. 7 is a diagram for explaining the order of selecting scanning lines in the second embodiment.

In the second embodiment, the screen has a total of k scanning lines, an upper region including a pixel portion corresponding to n scanning lines at the top of the screen, and m scanning lines at the bottom of the screen. And a lower region including a pixel portion corresponding to. In the upper region of the screen, interlaced scanning is performed at intervals of three, that is, at a pitch of 3, and in the lower region of the screen, continuous scanning, that is, scanning at a pitch of 1, is performed.

In order to facilitate comparison between FIG. 6 and FIG. 7, it is assumed that the total number of scanning lines is the same and k = n + m. The broken line in FIG. 6 indicates a scanning line corresponding to a pixel that is not updated. A solid line indicates a scanning line corresponding to the pixel to be updated.

First, in the first image, at time t0 to t1, a scanning line is selected as shown in FIG. In the upper region, the scanning lines are selected one by one in order of the first, fourth, seventh, tenth,... At two intervals. Subsequently, in the lower region, the n + th
1, the (n + 2) th, (n + 3) th, (n + 4)...
Books are selected consecutively.

In the display of the second image at times t1 to t2, as shown in FIG. 7B, in the upper region, the scanning lines are arranged one by one in the order of second, fifth, eighth, eleventh,. Selected. Subsequently, in the lower region, the (n + 1) th to (n + m) th scanning lines are sequentially selected one by one, as in FIG. 7A.

In the display of the third image at times t2 to t3, as shown in FIG.
The scanning lines are selected one by one in the order of the third, sixth, ninth, twelfth,.... Subsequently, in the lower region, the (n + 1) th to (n + m) th scanning lines are sequentially selected one by one in the same manner as in FIG. Thereafter, scanning lines are selected in the same order, and the screen is updated.

As described above, in the second embodiment, the image quality of a moving image and the like is improved as in the first embodiment by providing a screen area for performing interlaced scanning with a scanning line selection interval at a part of the screen. Can be done. This is particularly effective when the number of scanning lines is large.

Third Embodiment In the third embodiment, the liquid crystal display device is different from the first embodiment in that a scanning line is selected at every other interlace scanning interval in the upper area of the screen shown in FIG. Different from the case of mode 2. The lower area of the screen is composed of pixels corresponding to m scanning lines, and the number k of scanning lines of the entire screen
Is the same as in the second embodiment in that k = n + m.

FIG. 8 is a diagram for explaining the order in which scanning lines are selected in the third embodiment. FIG. 8A is a diagram corresponding to the first image. FIG. 8B is a diagram corresponding to the second image.

At times t0 to t1, selection of a scanning line as shown in FIG. 8A is performed at the time of displaying the first image.

In the upper area of the screen, the scanning lines are spaced at one interval, that is, at the pitch 2, the first, third, fifth, and
.., (N-3) th and (n-1) th scanning lines are sequentially selected one by one. The selection of the scanning line is updated at a cycle of 2H. Further, when the selection of the scanning line is switched, a timing loss α occurs in which none of the scanning lines is selected.

This α is about 20% of one horizontal period. Therefore, it is about 6 μs. Subsequently, in the lower area of the screen, the (n + 1) -th to (n)
+ M) are sequentially selected one by one. That is,
The pitch for selecting the scanning line is 1. Scan line selection is 1H
The timing is updated periodically, and a timing loss α occurs when the selection of the scanning line is switched as in the case of the upper region.

Referring to FIG. 8B, when the second image is displayed at times t1 to t2, the second and fourth images are spaced at one pitch in the upper area of the screen, that is, at a pitch of two. , The sixth,..., (N−2) th, and n-th scanning lines are sequentially selected one by one. The switching cycle of the selection of the scanning line is 2H, and the timing loss occurring at the time of switching is α as in the case of the first image.

Subsequently, in the lower area of the screen, the first
As in the case of the image, the (n + 1) th to (n + m) th scanning lines are sequentially selected one by one. The switching period of the scanning line selection is 1H, and the timing loss that occurs when the selection is switched is α as in the case of the first image.

Thereafter, the scanning sequence shown in FIGS. 8A and 8B is alternately repeated to sequentially update the screen.

In the third embodiment, the scanning line selection switching period in the upper region of the screen is 2H, and the scanning line selection switching period in the lower region of the screen is 1H. In this case, the time required for updating the entire screen is kH, as shown in FIG.
2. There is no difference from the conventional scanning line selection method shown in FIG.

However, when the selection of each scanning line is switched, a timing loss α occurs, and the time for substantially charging each pixel portion is reduced. For example, FIG.
At the time of displaying the image shown in FIG. 8B, the charging time of each pixel portion of the scanning line in the upper region of the screen is 2H-α per two images, whereas in the lower region of the screen, FIG. H-α is charged twice in each of (a) and FIG. 8 (b). That is, the total charging time in the lower area of the screen is 2H-2α per two images.

That is, the timing loss is smaller and the charging efficiency is higher in the upper region of the screen. Further, since the driving frequency is lowered, the power consumption is reduced accordingly.

However, by skipping scanning lines,
The ability of the display to follow the movement of the screen is poor.

However, generally, the human eye has a low resolution (resolution) with respect to a moving object. Therefore, the entire image can be rewritten faster by interlaced scanning even if a shift occurs between the upper and lower lines, as compared with the case where the charging is sufficiently performed for each line and the screen updating time is extended to complete one frame. If it is a video, it looks more natural.

As described above, in the third embodiment, a screen with a wide scanning interval is provided and the selection time is lengthened to increase the charging efficiency and reduce the power consumption.

[Fourth Embodiment] In the fourth embodiment, as in the third embodiment, the scanning line n at the top of the screen is set.
In the upper region including the pixel corresponding to the book, the selection of the scanning line is switched every 2H, and the interval of the interlaced scanning is set at every other line.
That is, the selection of the scanning line is performed at the pitch 2.

In the lower region including pixels corresponding to m scanning lines at the bottom of the screen, the selection of the scanning lines is switched every 1H, and the scanning lines are successively and sequentially selected. The case where the line selection pitch is 1 is shown as an example. Note that the number of scanning lines on the entire screen is k,
k = n + m.

FIG. 9 is a diagram for explaining the order in which scanning lines are selected in the fourth embodiment. FIG. 9 (a),
(B), (c), and (d) are the first, second, third,
It is a figure corresponding to a 4th image.

At the time of displaying the first image, selection of a scanning line as shown in FIG. 9A is performed.

In the upper area of the screen, the scanning lines are sequentially arranged at intervals of one line, and the first, third, fifth,..., (N-3), and (n-1) th scanning lines are arranged in this order. Books are selected one by one. The selection of the scanning line is updated at a cycle of 2H.

Subsequently, in the lower area of the screen, the (n + 1) th to (n + m) th scanning lines arranged continuously are sequentially selected one by one. The selection of the scanning line is updated in the 1H cycle.

In FIG. 9A, a negative image signal is applied to a signal line in the upper region of the screen. Therefore, when the first image is displayed, the polarity of the signal held by each pixel unit updated in the upper region of the screen is:
The polarity is reversed from positive to negative.

Referring to FIG. 9B, at the time of displaying the second image, in the upper region of the screen, the second image is spaced apart by one line.
The fourth, sixth,..., (N−2), and n-th scanning lines are sequentially 1
Books are selected one by one. The point that the switching cycle of the scanning line selection is 2H is the same as that at the time of displaying the first image.

Subsequently, in the lower area of the screen, the first
As in the case of displaying an image, the (n + 1) th to (n + m) th scanning lines are sequentially selected one by one.

In FIG. 9B, a negative image signal is applied to the signal line in the upper area of the screen. Therefore, at the time of displaying the second image, the polarity of the signals held by all the pixel units in the upper region of the screen is inverted from the positive polarity to the negative polarity.

At the time of displaying the third image, a scanning line is selected as shown in FIG.

In the upper area of the screen, the scanning lines are sequentially arranged at intervals of one line, and are sequentially 1st, 3rd, 5th,..., (N−3), (n−1) th in order. Books are selected one by one. The selection of the scanning line is updated at a cycle of 2H.

Subsequently, in the lower area of the screen, the (n + 1) th to (n + m) th scanning lines arranged continuously are sequentially selected one by one. The selection of the scanning line is updated in the 1H cycle.

In FIG. 9C, a positive image signal is applied to the signal line in the upper area of the screen. Therefore, when the first image is displayed, the polarity of the signal held by each pixel unit updated in the upper region of the screen is:
The polarity is reversed from negative to positive.

Referring to FIG. 9D, at the time of displaying the second image, in the upper region of the screen, the second and third images are spaced apart by one line.
The fourth, sixth,..., (N−2), and n-th scanning lines are sequentially 1
Books are selected one by one. The switching period of the scanning line selection is 2H as in the case of the third image.

Subsequently, in the lower area of the screen, the third
As in the case of the image, the (n + 1) th to (n + m) th scanning lines are sequentially selected one by one.

In FIG. 9D, a positive image signal is applied to the signal line in the upper area of the screen. Therefore, at the time of displaying the second image, the polarities of the signals held by all the pixel units in the upper region of the screen are inverted from the negative polarity to the positive polarity.

FIG. 10 is an operation waveform diagram for explaining actual operations of the scanning lines and signal lines in FIGS. 9 (a) to 9 (d).

FIG. 10 shows a case where the total number of scanning lines is 16 for simplicity of description, and only signal line D1 shows a typical waveform of signal lines.

Referring to FIGS. 3 and 10, at time t1, scanning line L1 is activated. Correspondingly, a signal corresponding to the negative image is supplied to the signal line D1.

Thereafter, at times t2, t3, and t4, the scanning lines L3, L5, and L7 are activated, respectively, and the signal line D1 is supplied with a negative signal corresponding to the image each time. The holding signal of the pixel portion existing at the intersection is updated.

In the period from time t1 to time t5, the selection of the scanning line is switched at a period of 2H, and the scanning lines are sequentially selected every other line by interlaced scanning.

At time t5 to t1A, the lower area of the screen is continuously scanned. The scanning lines L9 to L16 are sequentially selected one by one in the switching cycle 1H. A positive signal corresponding to the image signal is supplied to the signal line D1 in accordance with the selection of the scanning line, and the holding signal in each pixel portion is updated. The above is the operation waveform corresponding to FIG.

The operation waveform after time t1A corresponds to the operation waveform shown in FIG. The operation waveforms corresponding to FIGS. 9B and 9C are not shown.

During the period from time t1A to time t5A, the selection of the scanning line is switched at a cycle of 2H, and the scanning lines L2, L4, L6 and L8 are sequentially selected by the interlaced scanning. Further, in response to the selection of each scanning line, a signal of positive polarity corresponding to the image signal is supplied to the signal line D1, and the signal held by each pixel portion is updated.

After time t5A, the lower area of the screen is continuously scanned. The scanning lines are scanning lines L9-L at the switching cycle 1H.
16 are sequentially selected one by one. A positive signal corresponding to the image signal is supplied to the signal line D1 in accordance with the selection of the scanning line, and the holding signal in each pixel portion is updated.

In FIG. 10, the signal line D1 is shown as a representative of the signal lines, but signals having similar polarities corresponding to the respective pixels are also applied to other signal lines.

Since the characteristics of the liquid crystal are deteriorated when the direct current is continuously applied, it is necessary to change the polarity of the signal held in the pixel portion at a constant frequency. Charging the pixel portion with a signal of the opposite polarity requires a longer time than charging with a signal of the same polarity.

Therefore, in the fourth embodiment, a voltage is applied to the pixel portion corresponding to the scanning line having a long selection time by changing the polarity every scan every time the screen is updated. Thus, the deterioration of the characteristics of the liquid crystal is prevented.

Note that it is necessary to invert the polarity of the lower part of the screen where the inversion of the polarity is not performed at a cycle within a range where the liquid crystal does not deteriorate. In this case, the pixel portion becomes insufficiently charged immediately after the polarity is changed due to the short selection time of the scanning line, and the lower portion of the screen deteriorates in contrast and the like, but the upper portion of the screen is sufficiently charged so that the screen is sufficiently charged. The overall image quality is not degraded. In the fourth embodiment, by increasing the ratio of the pixel portion which changes the polarity for each scan to the entire screen with a long scanning line selection time, the liquid crystal deterioration is prevented and the image quality of the entire screen is improved. .

The transition of the polarity of the signal held by each pixel section of the entire screen based on the above waveform will be described.

FIG. 11 is a diagram for explaining the polarity of the signal held by each pixel unit when the first image is displayed.

FIG. 11 shows a state immediately after the selection of all the scanning lines described with reference to FIG. 9A is completed. For the sake of simplicity, a case where there are 16 scanning lines L1 to L16 and 20 signal lines D1 to D20 will be shown as an example. That is, this corresponds to the case where n = 8 and m = 8 in FIG.

Referring to FIG. 11, an arrow displayed in each pixel indicates the polarity of a signal held by each pixel portion, an upward arrow indicates a positive polarity, and a downward arrow indicates a negative polarity.

A scanning line corresponding to the pixel portion updated at the time of displaying the first image is marked with a circle. Also, 2
H indicates that the scanning line selection is switched in a 2H cycle, and 1H indicates that the scanning line selection is switched in a 1H cycle. Before the update of the first image, it is assumed that a positive polarity signal has been written to all the pixels.

In the first screen area corresponding to the scanning lines L1 to L8, odd-numbered scanning lines are sequentially selected, and a negative signal is applied to each pixel portion.

The second line corresponding to the scanning lines L9 to L16
In the screen area, the selection of the scanning lines is switched in the order of 1H from the scanning line L9, and each pixel is updated. At this time, the same positive polarity signal as the previously held data is supplied to each pixel unit.

FIG. 12 is a diagram for explaining the polarity of the signal held by each pixel unit when displaying the second image.

FIG. 12 corresponds to the state immediately after the selection of the scanning line in FIG. 9B is completed. In the first screen area corresponding to the scanning lines L1 to L8, the even-numbered scanning lines are sequentially selected and a negative signal is applied, and the polarity of the signal held by the corresponding pixel portion becomes negative. Therefore, in the first screen area, the polarities of the signals held by all the pixel units are negative.

In the second screen area corresponding to the scanning lines L9 to L16 at the bottom of the screen, the same screen updating as in FIG. 11 is performed.

FIG. 13 is a diagram for explaining the polarity of the signal held by each pixel unit when the third image is displayed.

FIG. 13 corresponds to the state immediately after the selection of the scanning line in FIG. 9C is completed. In the first screen area corresponding to the scanning lines L1 to L8, odd-numbered scanning lines are sequentially selected, and the signal held by the corresponding pixel portion is updated. The polarity of the signal of the pixel portion to be updated has a positive polarity, and the polarity of the signal held by the pixel portion corresponding to the odd-numbered scanning line is inverted.

In the second screen area corresponding to scanning lines L9 to L16, the same operation as in FIG. 11 is performed, and therefore description will not be repeated.

FIG. 14 is a diagram for explaining the polarity of the signal held by each pixel unit when the fourth image is displayed.

FIG. 14 corresponds to the state immediately after the selection of the scanning line described with reference to FIG. 9D.

In the first screen area corresponding to the scanning lines L1 to L8, the even-numbered scanning lines are sequentially selected, and a positive signal is written to the corresponding pixel portion. Therefore, the polarity of the signal held by each pixel unit corresponding to the even-numbered scanning line is also inverted, and the polarity of the signal held by all the pixel units in the first screen region becomes positive.

In the second screen area corresponding to scanning lines L9 to L16, the same operation as in FIG. 11 is performed, and therefore description thereof will not be repeated.

Therefore, in the first screen area,
An image with good contrast is obtained.

[Embodiment 5] FIG. 15 shows Embodiment 5 of the present invention.
FIG. 3 is a diagram for explaining an order in which scanning lines are selected in FIG. FIGS. 15 (a) to 15 (h) show first to first, respectively.
This shows the order in which the scanning lines are selected when the eighth image is displayed.

In the fifth embodiment, similarly to the third embodiment, the scanning interval of the screen area having a long selection time of the scanning line is set to be every other line, that is, the pitch is 2, and the scanning is performed in the screen area having a short selection time. Continuous, that is, the pitch is 1
An example in which scanning is performed by the following will be described. It is also assumed that the number of scanning lines in the entire screen is k, and one screen is composed of a screen area of n scanning lines at the top of the screen and a screen area of n scanning lines at the bottom of the screen. Note that k = 2n.

Referring to FIG. 15 (a), at time t0 to time t1 when the first image is displayed and updated, the first, third, fifth, and fifth lines are separated by one in the upper region of the screen. .., (N-3) th and (n-1) th scanning lines are sequentially selected.
Subsequently, in the lower area of the screen, the (n + 1) th to (2n) th scanning lines are sequentially selected one by one. here,
In the upper area of the screen, the polarity of the applied signal is inverted, and in the lower area of the screen, a signal having the same polarity as the previous image is applied to each pixel unit.

Referring to FIG. 15B, times t1 to t2
, The second, fourth, sixth,..., (N−2), and n-th scanning lines are sequentially selected in the upper area of the screen. That is, in the upper region of the screen, the selection time per scanning line is long, and interlaced scanning is performed. In the upper region of the screen, a signal of negative polarity is given to each pixel portion in accordance with the selection of the scanning line,
The polarity of the signal held by each pixel portion to be updated is inverted from positive polarity to negative polarity.

Subsequently, in the lower area of the screen, the (n +
1) to (2n) th scanning lines are sequentially selected one by one.
The cycle at which the selection of the scanning line is switched at this time is 1H.

Referring to FIG. 15C, times t2 to t3
In, a third image is displayed. The top area of the screen
Continuous scanning is performed, and the first to n-th scanning lines are sequentially selected in the selection switching period 1H.

Subsequently, interlaced scanning is performed in the lower area of the screen, and the (n + 1) th, (n + 3),..., (2n-3), and (2n-1) th scanning lines are successively one. Selected for each. In the lower area of the screen, the cycle at which the selection of the scanning line is switched is 2H, the polarity of the applied signal becomes negative, and the polarity of the signal held by each updated pixel unit is inverted.

Referring to FIG. 15D, at times t3 to t4
, A fourth image is displayed. Regarding the upper region of the screen, the same operation as that of FIG.

In the lower area of the screen, the even-numbered scanning lines are sequentially selected in the selection switching cycle 2H. That is, the (n + 2) th, (n + 4) ..., (2n-2), (2n)
The scanning lines n) are sequentially selected one by one. In the lower area of the screen, a negative signal is applied to each pixel in accordance with the selection of the scanning line, and the polarity of the signal held by each pixel in the lower area of the screen changes from positive to negative. Invert.

FIGS. 15 (e) to 15 (h) show a case where the polarity of the signal held by the pixel portion of the screen is reversed from negative to positive.

Referring to FIG. 15 (e), at time t0 to t1 when the first image is displayed and updated, the first, third, fifth and fifth images are spaced at an interval in the upper area of the screen. .., (N-3) th and (n-1) th scanning lines are sequentially selected.
Subsequently, in the lower area of the screen, the (n + 1) th to (2n) th scanning lines are sequentially selected one by one. here,
In the upper area of the screen, the polarity of the applied signal is inverted, and in the lower area of the screen, a signal having the same polarity as the previous image is applied to each pixel unit.

Referring to FIG. 15F, times t1 to t2
When the second image is displayed, the second, fourth, sixth,..., (N−2), and n-th scanning lines are sequentially selected in the upper region of the screen. That is, in the upper region of the screen, the selection time per scanning line is long, and interlaced scanning is performed. In the upper region of the screen, a positive signal is applied to each pixel in accordance with the selection of the scanning line, and the polarity of the signal held by all the pixels in the upper region of the screen changes from negative to positive. Invert.

Subsequently, in the lower area of the screen, the (n +
1) to (2n) th scanning lines are sequentially selected one by one.
The cycle at which the selection of the scanning line is switched at this time is 1H.

Referring to FIG. 15 (g), times t2 to t3
In, a third image is displayed. The top area of the screen
Continuous scanning is performed, and the first to n-th scanning lines are sequentially selected in the selection switching period 1H.

Subsequently, interlaced scanning is performed in the lower area of the screen, and the (n + 1) th, (n + 3),..., (2n-3), and (2n-1) th scanning lines are successively provided. Selected for each. In the lower area of the screen, the cycle at which the selection of the scanning line is switched is 2H, the polarity of the applied signal becomes positive, and the polarity of the signal held by each updated pixel unit is inverted.

Referring to FIG. 15 (h), from time t3 to t4
, A fourth image is displayed. Regarding the upper region of the screen, the same operation as that of FIG. 15C is performed, and therefore description thereof will not be repeated.

In the lower area of the screen, the even-numbered scanning lines are sequentially selected in the selection switching cycle 2H. That is, the (n + 2) th, (n + 4) ..., (2n-2), (2n)
The scanning lines n) are sequentially selected one by one. In the lower area of the screen, a positive signal is given to each pixel in accordance with the selection of the scanning line, and the polarity of the signal held by all the pixels in the lower area of the screen changes from negative to positive. Invert.

FIGS. 16 and 17 are flowcharts for explaining the procedure for updating the screen in the fifth embodiment.

Referring to FIG. 16, first, in step S01
, The display of the (8S + 1) th image is started (S
Is a natural number).

Hereinafter, a group of pixel portions selected corresponding to each scanning line will be referred to as a line.

At step S02, the first
The odd lines in the area are sequentially updated with negative polarity. This update time is performed at a cycle of 2H per line. Step S
At 03, all lines in the second area at the bottom of the screen are sequentially updated with positive polarity. At this time, the selection of the scanning line is switched at a pitch of 1 and an update time of 1H per line. Then, in step S04, the (8S +
1) Display of the image is completed.

Steps S01 to S04 are the same as those in FIG.
This corresponds to (a). Subsequently, in step S05,
The display of the (8S + 2) th image is started. Step S0
At 6, the even lines in the first area at the top of the screen are sequentially updated with negative polarity. At this time, the selection of the scanning line has a pitch of 2
The update time is 2H per line.

Subsequently, in step S07, all lines in the second area at the bottom of the screen are sequentially updated with positive polarity. The update time at this time is 1H per line. Then, in step S08, the display of the (8S + 2) th image is completed.

Steps S05 to S08 are the same as those in FIG.
This corresponds to (b). Subsequently, in step S11,
The display of the (8S + 3) th image is started.

At step S12, the first
All lines in the area are updated sequentially with negative polarity. At this time, the selection time is switched at 1H per line. In step S13, the odd lines in the second area at the bottom of the screen are sequentially updated with negative polarity. This update time is 1
This is performed at a cycle of 2H per line. And step S
At 14, the display of the (8S + 3) th image is completed.

Steps S11 to S14 are the same as those in FIG.
This corresponds to (c). Subsequently, in step S15,
The display of the (8S + 4) th image is started.

At step S16, the first
All lines in the area are updated sequentially with negative polarity. The update time at this time is 1H per line. Step S1
At 7, the even lines in the second area at the bottom of the screen are sequentially updated with negative polarity. The update time at this time is 2 per line
H. Then, in step S18, the (8S +
4) Display of the image is completed.

Steps S15 to S18 are the same as those in FIG.
(D). Subsequently, referring to FIG. 17, in step S21, display of the (8S + 5) th image is started.

In step S22, the first screen at the top of the screen
The odd lines in the area are sequentially updated with positive polarity. This update time is performed at a cycle of 2H per line. Step S
At 23, all lines in the second area at the bottom of the screen are sequentially updated with negative polarity. At this time, the selection time is switched at 1H per line. And step S
At 24, the display of the (8S + 5) th image is completed.

Steps S21 to S24 are the same as those in FIG.
(E). Subsequently, in step S25,
The display of the (8S + 6) th image is started. Step S2
At 6, the even lines in the first area at the top of the screen are sequentially updated with positive polarity. The update time at this time is 2 per line
H.

Subsequently, in step S27, all the lines in the second area at the bottom of the screen are sequentially updated with the negative polarity. The update time at this time is 1H per line. Then, the display of the (8S + 6) th image is completed in step S28.

Steps S25 to S28 are the same as those in FIG.
This corresponds to (f). Subsequently, in step S31,
The display of the (8S + 7) th image is started.

In step S32, the first screen at the top of the screen
All lines in the area are updated sequentially with positive polarity. At this time, the selection time is switched at 1H per line. In step S33, odd lines in the second area at the bottom of the screen are sequentially updated with positive polarity. This update time is 1
This is performed at a cycle of 2H per line. And step S
At 34, the display of the (8S + 7) th image is completed.

Steps S31 to S34 are the same as those in FIG.
(G). Subsequently, in step S35,
The display of the (8S + 8) th image is started.

In step S36, the first screen at the top of the screen
All lines in the area are updated sequentially with negative polarity. The update time at this time is 1H per line. Step S3
At 7, the even lines in the second area at the bottom of the screen are sequentially updated with positive polarity. The update time at this time is 2 per line
H. Then, in step S38, the (8S +
8) Display of the image is completed.

Steps S35 to S38 are the same as those in FIG.
(H). Thereafter, steps S01 to S38 are repeated.

Next, a change in polarity of a signal held by each pixel portion will be described. FIG. 18 is a diagram for explaining the polarity of the signal held by each pixel unit when the first image is displayed. FIG. 18 corresponds to a state immediately after the selection of the scanning line shown in FIG.

At the time of displaying the image before this image, it is assumed that all the pixel sections hold the signal of the positive polarity.
Note that an upward arrow in the figure indicates a positive signal, and a downward arrow indicates a negative signal.

Referring to FIG. 18, scanning line L1 at the top of the screen
In L8, the odd-numbered scanning lines are sequentially selected, and the corresponding pixels are updated. The cycle of this update is 2H.
At the time of updating, a negative polarity signal is written into each pixel portion, and the polarity of the signal held by the updated pixel portion is inverted.

In the lower area of the screen corresponding to the scanning lines L9 to L16, all the scanning lines are sequentially selected. The selection switching cycle at this time is 1H.

Since a positive polarity signal is written in the lower area of the screen, the polarity of the signal held by each pixel portion is not inverted.

FIG. 19 is a diagram for explaining the polarity of the signal held by each pixel unit when the second image is displayed.

FIG. 19 corresponds to a state immediately after the selection of the scanning line in FIG. 15B is completed. Referring to FIG. 19, in the upper region of the screen, even-numbered scanning lines are sequentially selected, and the signal held by the corresponding pixel portion is updated. At this time, the polarity of the signal to be written is negative, and the polarity of the signal held by each pixel portion is inverted. In the upper region of the screen, the polarity of the signal held by each pixel portion is all negative.

Subsequently, the display in the lower area of the screen is updated. The scanning lines L9 to L16 are sequentially selected, and positive polarity signals are sequentially written to corresponding pixel portions. The selection switching cycle at this time is 1H.

FIG. 20 is a diagram for explaining the polarity of the signal held by each pixel unit when the third image is displayed.

FIG. 20 corresponds to the state immediately after the selection of the scanning line in FIG. 15C is completed. Referring to FIG. 20, in the upper region of the screen, scanning lines L1 to L8 are sequentially selected, and a signal of negative polarity is written to each pixel portion. At this time,
The switching period of the scanning line selection is 1H.

In the lower part of the screen, only the odd-numbered scanning lines are sequentially selected, and a signal of negative polarity is written to the corresponding pixel portion. At this time, the scanning line selection switching period is 2H.

FIG. 21 is a diagram for explaining the polarity of the signal held by each pixel unit when the fourth image is displayed.

FIG. 21 corresponds to a state immediately after the selection of the scanning line in FIG. 15D is completed. Referring to FIG. 21, an operation similar to that of FIG. 20 is performed in a region corresponding to scanning lines L1 to L8 at the top of the screen, and therefore description thereof will not be repeated.

In the lower area of the screen, only the even-numbered scanning lines are sequentially selected. The switching cycle of this selection is 2H
It is. When a scanning line is selected, a signal of negative polarity is written to the corresponding pixel portion. Therefore, in FIG. 21, the polarity of the signal held by all the pixel units on the screen is negative.

Through the procedures shown in FIGS. 18 to 21, the polarities of the signals held by the respective pixel portions in all the screen areas are inverted. This is indicated by the inversion of the arrow in the figure on each pixel portion from upward to downward.

FIG. 22 is a diagram for explaining the polarity of the signal held by each pixel unit when the fifth image is displayed.

FIG. 22 corresponds to a state immediately after the selection of the scanning line in FIG. Referring to FIG. 22, in the scanning lines L1 to L8 at the top of the screen, odd-numbered scanning lines are sequentially selected, and the corresponding pixels are updated. The cycle of this update is 2H. At the time of updating, a positive polarity signal is written into each pixel portion, and the polarity of the signal held by the updated pixel portion is inverted.

In the lower area of the screen corresponding to the scanning lines L9 to L16, all the scanning lines are sequentially selected. The selection switching cycle at this time is 1H.

Since a negative signal is written in the lower area of the screen, the polarity of the signal held by each pixel portion is not inverted.

FIG. 23 is a diagram for explaining the polarity of the signal held by each pixel unit when displaying the sixth image.

FIG. 23 corresponds to the state immediately after the end of the selection of the scanning line shown in FIG. Referring to FIG. 23, in the upper region of the screen, the even-numbered scanning lines are sequentially selected, and the signal held by the corresponding pixel portion is updated. At this time, the polarity of the written signal is positive,
The polarity of the signal held by each pixel unit is inverted. In the upper region of the screen, the polarity of the signal held by each pixel portion is all positive.

Subsequently, the display in the lower area of the screen is updated. The scanning lines L9 to L16 are sequentially selected, and a negative signal is sequentially written to the corresponding pixel portion. The selection switching cycle at this time is 1H.

FIG. 24 is a diagram for explaining the polarity of the signal held by each pixel unit when the seventh image is displayed.

FIG. 24 corresponds to a state immediately after the selection of the scanning line shown in FIG. Referring to FIG. 24, scanning lines L1 to L8 are sequentially selected in the upper region of the screen, and a signal of positive polarity is written to each pixel portion. At this time,
The switching period of the scanning line selection is 1H.

In the lower part of the screen, only odd-numbered scanning lines are sequentially selected, and a signal of positive polarity is written to the corresponding pixel portion. At this time, the scanning line selection switching period is 2H.

FIG. 25 is a diagram for explaining the polarity of the signal held by each pixel unit when the eighth image is displayed.

FIG. 25 corresponds to a state immediately after the selection of the scanning line shown in FIG. Referring to FIG. 25, in a region corresponding to scanning lines L1 to L8 at the top of the screen, the same operation as that of FIG. 24 is performed, and therefore description thereof will not be repeated.

In the lower area of the screen, only even-numbered scanning lines are sequentially selected. The switching cycle of this selection is 2H
It is. When a scanning line is selected, a signal of positive polarity is written to the corresponding pixel portion. Therefore, in FIG. 25, the polarity of the signal held by all the pixel units on the screen becomes positive.

Through the procedures shown in FIGS. 22 to 25, the polarities of the signals held by the respective pixel portions in all the screen areas are inverted. This is indicated by the inversion of the arrow in the figure on each pixel portion from downward to upward.

As described above, in the fifth embodiment, the selection time of the scanning line corresponding to the pixel portion charged with the opposite polarity is extended, and the scanning corresponding to the pixel portion charged without changing the polarity is performed. Shorten the line selection time. Then, by replacing and moving the screen area of the pixel portion to be charged with the opposite polarity after a lapse of a predetermined time, it is possible to solve the shortage of the charging time of the entire screen and prevent the liquid crystal from being deteriorated.

[Embodiment 6] FIG. 26 shows Embodiment 6 of the present invention.
FIG. 6 is a diagram for explaining how to select a scanning line on a screen in FIG.

Referring to FIG. 26, in the sixth embodiment, the screen is further divided, and a scanning line is selected by a different method for each divided area. FIG. 26 shows a case where the screen is divided into four as an example. Each screen area is composed of a pixel portion corresponding to n scanning lines, and the number k of all the scanning lines
= 4 · n.

FIG. 27 is a diagram for explaining a scanning line selection order according to the sixth embodiment. FIG. 27 (a)
FIG. 27B is a diagram corresponding to the first image, and FIG. 27B is a diagram corresponding to the second image.

Referring to FIGS. 26 and 27 (a), assuming that the screen is divided into first, second, third, and fourth screen areas from the top of the screen, first, in the first screen area, Odd-numbered scanning lines are sequentially selected one by one. At this time, the scanning line is selected at a pitch of 2, and the selection switching cycle is 2H.
It is. That is, the first, third,..., (N−1) th scanning lines are sequentially selected one by one.

In the second screen area, n scanning lines are sequentially selected one by one. That is, the (n + 1) th to (2n) th scanning lines are continuously scanned at a pitch of one. The selection switching cycle at this time is 1H.

Next, in the third screen area, odd-numbered scanning lines are sequentially selected in the same manner as in the first screen area.
That is, only the odd-numbered scanning lines are sequentially selected from the (2n + 1) th to (3n-1) th scanning lines. The selection of the scanning line at this time is performed at a pitch of 2, and the selection switching cycle is 2H.

In the fourth screen area, continuous scanning is performed, and the (3n + 1) th to (4n) th scanning lines are sequentially selected one by one. The selection switching cycle at this time is 1H.

In FIG. 27B, when selecting the scanning lines at the time of displaying the second image, only the even-numbered scanning lines are sequentially selected in the first screen area. At this time, the switching period of the selection of the scanning line is 2H. In the second screen area, FIG.
Continuous scanning is performed in the same manner as in FIG.

In the third screen area, even-numbered scanning lines are sequentially selected. The switching period of the scanning line at this time is 2H. In the fourth screen area, FIG.
Continuous scanning is performed as in (a).

FIG. 28 is a diagram for explaining the polarities held by the respective pixel portions when the first image is displayed.

In FIG. 28, the scanning line is L for simplicity of explanation.
1 to L16, and 20 signal lines D1 to D20.
Shows the case of a book. 26 and FIG. 27, n =
4 corresponds to the case. Also, it is assumed that all the pixel units hold the signal of the positive polarity during the previous image display.

In the first screen area including pixels corresponding to the scanning lines L1 to L4, odd-numbered scanning lines are sequentially selected. The switching period for selecting the scanning line is 2H.
When the scanning line is selected, a signal of negative polarity is written to each pixel portion by the signal lines D1 to D20.

In the second screen area including the pixels corresponding to the scanning lines L5 to L8, all the scanning lines are sequentially selected. The selection is switched in a cycle of 1H.
In the second screen area, the polarity of the signal given from the signal line is positive and the polarity of the signal held by each pixel portion is not inverted.

In the third screen area including the pixels corresponding to the scanning lines L9 to L12, like the first screen area,
Odd-numbered scanning lines are sequentially selected, and a negative signal is written to the corresponding pixel portion. The selection switching cycle at this time is 2
H.

In the fourth screen area including pixels corresponding to the scanning lines L13 to L16, all the scanning lines are sequentially selected. The selection switching cycle at this time is 1H.
The polarity of the signal to be written is positive, and the polarity of the signal held by each pixel portion is not inverted.

FIG. 29 is a diagram for explaining the polarity of the signal held by each pixel unit when the second image is displayed.

Referring to FIG. 29, in the first screen area, even-numbered scanning lines are sequentially selected, and a signal of negative polarity is written. The selection switching cycle at this time is 2H.

In the second screen area, the same operation as the operation shown in FIG. 28 is performed, and therefore description will not be repeated.

In the third screen area including pixels corresponding to the scanning lines L9 to L12, even-numbered scanning lines are sequentially selected. The selection switching cycle at this time is 2H. The signal to be written has a negative polarity.

In the fourth screen area including pixels corresponding to scanning lines L13 to L16, the operation described with reference to FIG. 28 is repeated, and therefore description will not be repeated.

FIG. 30 is a diagram for explaining the polarity of the signal held by each pixel when the third image is displayed.

Referring to FIG. 30, in the first screen area including the pixel portions corresponding to the scanning lines L1 to L4, all the scanning lines are sequentially selected. This selection is switched by 1H
Is performed in a cycle of In the first screen area, the polarity of the signal supplied from the signal line is negative, and the polarity of the signal held by each pixel portion is not inverted.

In the second screen area including the pixel portions corresponding to the scanning lines L5 to L8, odd-numbered scanning lines are sequentially selected. The switching period for selecting the scanning line is 2H. When the scanning line is selected, a signal of negative polarity is written to each pixel portion by the signal lines D1 to D20.

In the third screen area including the pixels corresponding to the scanning lines L9 to L12, all the scanning lines are sequentially selected. The selection switching cycle at this time is 1H. The polarity of the signal to be written is negative, and the polarity of the signal held by each pixel portion does not reverse.

In the fourth screen area composed of the pixels corresponding to the scanning lines L13 to L16, the odd-numbered scanning lines are sequentially selected in the same manner as in the second screen area, and the corresponding pixel portion has a negative signal. Is written. The selection switching cycle at this time is 2H.

FIG. 31 is a diagram for explaining the polarity of the signal held by each pixel portion when the fourth image is displayed.

Referring to FIG. 31, in the first screen area, the operation shown in FIG. 30 is repeated, and therefore description will not be repeated.

In the second screen area, the even-numbered scanning lines are sequentially selected, and a negative polarity signal is written. The selection switching cycle at this time is 2H.

In the third screen area including pixels corresponding to scanning lines L9 to L12, the operation described with reference to FIG. 30 is repeated, and therefore description will not be repeated.

In the fourth screen area including pixels corresponding to the scanning lines L13 to L16, even-numbered scanning lines are sequentially selected. The selection switching cycle at this time is 2H.
The signal to be written has a negative polarity.

In this manner, the polarity of the signal held by the pixel portion is inverted after four screen updates.

Subsequently, in the same procedure, the polarity of the signal held by each pixel portion is inverted from negative polarity to positive polarity.
The polarity of the signal held by each pixel portion is repeated at regular intervals.

In the sixth embodiment, there are a plurality of screen areas each having a longer scanning line skip interval and a plurality of screen areas each having a smaller scanning line skip interval or continuously scanning a scanning line. By replacing these areas for each display image and displaying them, areas having different charging conditions are dispersed,
The charging of each pixel portion is made uniform, and an improvement in image quality can be expected.

The examples described in the first to sixth embodiments are effective for realizing a liquid crystal display device having a wide viewing angle using a ferroelectric liquid crystal or an antiferroelectric liquid crystal as a liquid crystal material. In the case where a twisted nematic liquid crystal is used as a liquid crystal material, the present invention is effective even when the number of scanning lines is increased to realize a high-definition screen and the charging time is insufficient.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[0265]

The liquid crystal display device according to any one of claims 1 to 4,
The screen update speed is increased, and it is possible to make the moving image look more natural.

According to the liquid crystal display device of the present invention, in addition to the effect of the liquid crystal display device of the first aspect, a screen area having a wide scanning interval is provided, and the selection time of the scanning line is lengthened. As a result, the charging efficiency can be increased and the power consumption can be reduced.

The liquid crystal display device according to the eighth aspect is the first aspect.
In addition to the effects provided by the liquid crystal display device described in 1 above, the shortage of the charging time of the entire screen and the prevention of liquid crystal deterioration are eliminated by replacing and moving the screen area of the pixel portion charged with the opposite polarity after a certain time has elapsed. be able to.

The liquid crystal display device according to the ninth and tenth aspects,
In addition to the effects of the liquid crystal display device according to claim 1,
The viewing angle can be widened.

The liquid crystal display device according to the eleventh aspect can improve the image quality when driving a screen having a large number of scanning lines, in addition to the effects of the liquid crystal display device according to the first aspect.

In the driving method of the liquid crystal display device according to the twelfth to fifteenth aspects, the updating speed of the screen is increased, and the moving image can be seen more naturally.

The method of driving a liquid crystal display device according to the sixteenth to seventeenth aspects has the effect of the driving method of the liquid crystal display device according to the thirteenth aspect, and further provides a screen area having a wide scanning interval and a scanning line. By increasing the selection time, charging efficiency is increased, and low power consumption can be achieved.

According to the driving method of the liquid crystal display device of the present invention, in addition to the effect obtained by the driving method of the liquid crystal display device of the present invention, the screen area of the pixel portion charged with the opposite polarity is kept for a predetermined time. By replacing and moving later, the shortage of the charging time for the entire screen can be solved and the deterioration of the liquid crystal can be prevented.

The method for driving a liquid crystal display device according to the nineteenth and twentieth aspects can provide a wide viewing angle in addition to the effect of the driving method for a liquid crystal display device according to the twelfth aspect.

According to the driving method of the liquid crystal display device of the present invention, in addition to the effect of the driving method of the liquid crystal display device of the present invention, the image quality can be improved when driving a screen having a large number of scanning lines. can do.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a liquid crystal display device 1 of the present invention.

FIG. 2 is a block diagram illustrating a schematic configuration of a liquid crystal panel 2 and a display control unit 8 in FIG.

FIG. 3 is an equivalent circuit diagram showing a part of the display panel 22 in FIG. 2 in an enlarged manner.

FIG. 4 is a diagram for explaining a manner in which a scanning line is selected on a screen according to the first embodiment.

FIG. 5 is a diagram for explaining an order in which scanning lines are selected in the first embodiment.

FIG. 6 is a diagram for explaining how to select a scanning line on a screen according to the second embodiment.

FIG. 7 is a diagram for explaining an order in which scanning lines are selected in the second embodiment.

FIG. 8 is a diagram for describing an order in which scanning lines are selected in the third embodiment. FIG. 8A is a diagram corresponding to the first image. FIG. 8B is a diagram corresponding to the second image.

FIG. 9 is a diagram for explaining an order in which scanning lines are selected in the fourth embodiment. 9 (a), (b),
(C), (d) is a figure corresponding to a 1st, 2nd, 3rd, 4th image, respectively.

FIG. 10 is an operation waveform diagram for explaining actual operations of scanning lines and signal lines in FIGS. 9 (a) to 9 (d).

FIG. 11 is a diagram for explaining the polarity of a signal held by each pixel unit when displaying a first image.

FIG. 12 is a diagram illustrating the polarity of a signal held by each pixel unit when displaying a second image.

FIG. 13 is a diagram for explaining the polarity of a signal held by each pixel unit when a third image is displayed.

FIG. 14 is a diagram illustrating the polarity of a signal held by each pixel unit when a fourth image is displayed.

FIG. 15 is a diagram for describing an order in which scanning lines are selected in the fifth embodiment. 15 (a) to 15
(H) shows the order in which the scanning lines are selected when displaying the first to eighth images, respectively.

FIG. 16 is a flowchart illustrating a procedure of updating a screen according to the fifth embodiment.

FIG. 17 is a flowchart illustrating a procedure of updating a screen according to the fifth embodiment.

FIG. 18 is a diagram for explaining the polarity of a signal held by each pixel unit when a first image is displayed.

FIG. 19 is a diagram for explaining the polarity of a signal held by each pixel unit when a second image is displayed.

FIG. 20 is a diagram for explaining the polarity of a signal held by each pixel unit when a third image is displayed.

FIG. 21 is a diagram for explaining the polarity of a signal held by each pixel unit when a fourth image is displayed.

FIG. 22 is a diagram for explaining the polarity of a signal held by each pixel unit when a fifth image is displayed.

FIG. 23 is a diagram for explaining the polarity of a signal held by each pixel unit when a sixth image is displayed.

FIG. 24 is a diagram for explaining the polarity of a signal held by each pixel unit when a seventh image is displayed.

FIG. 25 is a diagram for explaining the polarity of a signal held by each pixel unit when an eighth image is displayed.

FIG. 26 is a diagram for explaining how to select a scanning line on a screen in the sixth embodiment.

FIG. 27 is a diagram for describing a scanning line selection order in the sixth embodiment. FIG. 27A is a diagram corresponding to the first image, and FIG. 27B is a diagram corresponding to the second image.

FIG. 28 is a diagram for describing the polarity held by each pixel unit when displaying a first image.

FIG. 29 is a diagram for explaining the polarity of a signal held by each pixel unit when displaying a second image.

FIG. 30 is a diagram for explaining the polarity of a signal held by each pixel when a third image is displayed.

FIG. 31 is a diagram for explaining the polarity of a signal held by each pixel unit when a fourth image is displayed.

FIG. 32 is a view for explaining a method of driving a TFT liquid crystal panel using a conventional twisted nematic liquid crystal.

FIG. 33 is a diagram for explaining a driving order of scanning lines and a polarity of a signal applied to a pixel electrode through a signal line and a TFT. FIG. 33A is a diagram corresponding to the first image, and FIG. 33B is a diagram corresponding to the second image.

FIG. 34 is a diagram for explaining an example of a pseudo DC driving method. FIG. 34A is a diagram corresponding to the first image, FIG. 34B is a diagram corresponding to the second image, and FIG.
FIG. 34C is a diagram corresponding to the third image, and FIG.
Is a diagram corresponding to the fourth image.

FIG. 35 is a flowchart showing the operation of the conventional pseudo DC driving method.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 liquid crystal display device, 2 liquid crystal panel, 8 display signal control unit, 4 light sources, 6 light source drive unit, 10 inversion circuit, 14
X driver, 16 shift register, 18 sample hold circuit, 12 display control circuit, 20 Y driver,
L1 to L16 scanning lines, D1 to D20 signal lines, 22 display panels, 34 switching elements, 44 pixel electrodes,
46 counter electrode, 32 pixel section.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/36 G09G 3/36 H04N 5/66 102 H04N 5/66 102A F term (reference) 2H093 NA34 NA43 NC10 NC22 NC23 NC34 ND04 ND13 ND39 ND52 NF05 NF17 NF20 5C006 AA01 AC02 AC11 AC15 AC27 AC29 AF42 AF44 AF71 BA12 BA13 BB14 BB16 BC03 BC12 BF03 BF11 FA12 FA34 FA47 FA55 5C058 AA08 AB06 AB07 BA01 BA06 5C080 ADD DD07 DD DD DD JJ06 JJ07 5C094 AA02 AA06 AA12 AA13 AA22 AA37 BA03 BA45 BA49 CA19 EA04 EA07 GA10

Claims (21)

[Claims] 1. A liquid crystal display device, comprising: a liquid crystal material; a pair of substrates sandwiching the liquid crystal material; a counter electrode provided on at least one of the pair of substrates; A plurality of pixel electrodes for controlling the state of a portion of the liquid crystal material corresponding to the pixel by a potential difference applied to the counter electrode, and A plurality of scanning lines for selecting a row of the pixel electrodes to be arranged, and a signal arranged so as to intersect with the plurality of scanning lines and held as the potential difference between the pixel electrodes and a counter electrode A plurality of signal lines transmitting an update signal for updating the plurality of scanning lines, and a plurality of signal lines are provided corresponding to intersections of the plurality of scanning lines and the plurality of signal lines, respectively. A plurality of switching elements for transmitting the scan signal to the pixel electrode; and a screen drive unit that selects the scan line and provides the update signal to the plurality of signal lines. The plurality of scanning lines corresponding to a display area are sequentially selected at a first pitch, and the plurality of scanning lines corresponding to a second display area on the screen are sequentially selected at a second pitch different from the first pitch. LCD display to choose. 2. The first pitch is for the n scanning lines (n is a natural number of 2 or more), and the second pitch is for the m scanning lines (m is n).
The liquid crystal display device according to claim 1, wherein a smaller natural number is used. 3. The liquid crystal display device according to claim 2, wherein the second pitch is equivalent to one scanning line. 4. The liquid crystal display device according to claim 2, wherein the second pitch is equal to or more than two scanning lines. 5. The screen drive section selects the plurality of scanning lines in the first display area for a first selection time per one line, and selects the plurality of scanning lines in the second display area. 3. The liquid crystal display device according to claim 2, wherein one scanning line is selected in a second selection time shorter than the first selection time. 6. The screen driving unit, when selecting the plurality of scanning lines in the first display area, applies an update signal having a polarity opposite to that of an update signal given at the time of displaying a previous image to the plurality of signal lines. The liquid crystal display device according to claim 5, which is provided. 7. The screen driver outputs a polarity inversion signal for controlling the polarity of the update signal and a selection control signal for controlling selection of the scanning line based on a synchronization signal and a clock signal corresponding to a display image. A display control circuit that receives an image input signal corresponding to the display image, and performs a polarity inversion in accordance with the polarity inversion signal; and receives and holds an output of the polarity inversion circuit and holds the plurality of signals. The liquid crystal display device according to claim 5, further comprising: a signal line driving circuit that supplies an update signal to the line. 8. The liquid crystal display device repeatedly displays a first image group and a second image group on the screen in a predetermined order, wherein the first image group is a first display image. When displaying the first display image, the number of scanning lines corresponding to the first pitch is set to n (n is a natural number of 2 or more), and the scanning lines corresponding to the second pitch are displayed. M
(Where m is a natural number smaller than n), the second image group is such that the number of scanning lines corresponding to the first pitch is m and the number of scanning lines corresponding to the second pitch is m The liquid crystal display device according to claim 1, comprising at least a second display image indicated by n. 9. The liquid crystal material is a ferroelectric liquid crystal,
A liquid crystal display device according to claim 1. 10. The liquid crystal display device according to claim 1, wherein said liquid crystal material is an antiferroelectric liquid crystal. 11. The liquid crystal display device according to claim 1, wherein said liquid crystal material is a twisted nematic liquid crystal. 12. A method for driving a liquid crystal display device, comprising: a liquid crystal material; a pair of substrates sandwiching the liquid crystal material; and a counter electrode provided on at least one of the pair of substrates.
A plurality of pixel electrodes provided in a matrix corresponding to the pixels of the liquid crystal display device, and controlling a state of a portion of the liquid crystal material corresponding to the pixels by a potential difference applied to the counter electrode; A plurality of scanning lines for selecting each row of the pixel electrodes arranged along the horizontal direction of the screen, and arranged so as to intersect with the plurality of scanning lines, between the pixel electrode and the counter electrode. A plurality of signal lines transmitting an update signal for updating a signal held as the potential difference; and a plurality of signal lines provided corresponding to intersections of the plurality of scanning lines and the plurality of signal lines, respectively, and activated by the scanning lines. A plurality of switching elements for transmitting the update signal to the pixel electrode, wherein the plurality of switching elements correspond to a first display area on the screen. Sequentially selecting a scanning line at a first pitch and displaying an image on the first display area; and changing the plurality of scanning lines corresponding to a second display area on the screen from the first pitch. Sequentially selecting at a second pitch and displaying an image in the second display area. 13. The first pitch is for the n scanning lines (n is a natural number of 2 or more), and the second pitch is for the m scanning lines (m is n).
The method of driving a liquid crystal display device according to claim 12, wherein a smaller natural number is used. 14. The method according to claim 13, wherein the second pitch is equivalent to the one scanning line. 15. The method according to claim 13, wherein the second pitch is equal to or more than the two scanning lines. 16. The step of displaying an image in the first display area includes the step of selecting the plurality of scanning lines in the first display area per line at a first selection time, The step of displaying an image in the second display area includes the step of selecting the plurality of scanning lines in the second display area per second for a second selection time shorter than the first selection time. 14. The method for driving a liquid crystal display device according to claim 13. 17. The method of displaying an image in the first display area, comprising: when selecting the plurality of scanning lines in the first display area, updating an update signal having a polarity opposite to an update signal given at the time of displaying a previous image. 17. The method of driving a liquid crystal display device according to claim 16, further comprising a step of applying a signal to the plurality of signal lines. 18. The liquid crystal display device according to claim 1, further comprising:
And a second image group are repeatedly displayed in a predetermined order, and the first image group is a scanning line corresponding to the first pitch when the first display image is displayed. Is defined as n (n is a natural number of 2 or more), and the number of scanning lines corresponding to the second pitch is defined as m.
(Where m is a natural number smaller than n), the second image group is such that the number of scanning lines corresponding to the first pitch is m and the number of scanning lines corresponding to the second pitch is m 13. At least a second display image indicated by n.
3. The method for driving a liquid crystal display device according to item 1. 19. The method according to claim 12, wherein the liquid crystal material is a ferroelectric liquid crystal. 20. The method according to claim 12, wherein the liquid crystal material is an antiferroelectric liquid crystal. 21. The driving method according to claim 12, wherein the liquid crystal material is a twisted nematic liquid crystal.