JPH0328824A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To obtain high-quality images which are free from unequal display by providing the broad scanning electrodes corresponding to both of the divided signal electrodes divided to the parts which divide signal electrodes to above and below. CONSTITUTION:The signal electrodes x are bisected to above and below. The broad scanning electrodes YN formed broad in the width of the electrodes in order to intersect the electrodes respectively with the upper and lower divided signal electrodes x1 to xM, X'1 to X'M. The scanning electrodes Y1 to Y2N-1 are successively selected in order from the scanning electrode Y1 and the scan ning electrode Y2N-1 toward the scanning electrode YN. The scanning of one screen is ended by selecting the scanning electrode YN. Picture elements c1, c2, to cM-1, d1, d2 to dM1, dM are, therefore, constituted of one piece of the scanning electrodes YN by selecting the scanning electrodes Y1 to Y2N-1. Since the scanning electrode YN is also formed in the parts e1, e2 to e*M=1, eM where the scanning electrode x is divided, the generation of unequal images by a difference in the electric field intensity is obviated. The high-quality images are obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a liquid crystal display device in which electrodes are arranged in a matrix so as to face each other.

[Conventional technology]

In a liquid crystal display device used in liquid crystal televisions, etc., scanning electrodes to which scanning signals are supplied and signal electrodes to which display signals are supplied are arranged so as to cross each other and face each other, and the liquid crystal material is It changes the orientation of liquid crystal molecules to display images such as characters and figures.

In such a conventional liquid crystal display device, as shown in FIG. 4, M signal electrodes X extending vertically and divided into two vertically, and 2N scanning electrodes Y extending horizontally intersect with each other. The signal electrodes X and scanning electrodes Y are arranged facing each other with a predetermined gap therebetween, and a liquid crystal material is sealed in the gap between the signal electrodes X and scanning electrodes Y. That is, the signal electrode X is divided into M divided signal electrodes XI-X? I and M divided signal electrodes XI1
The scan electrode Y consists of 2N scan electrodes Y,
−． - Consists of Y2N.

These scan electrodes Y1 to Y2N are scan electrodes Y1. Y
8+1→Y2, Y)i*2→...Y. ,Y2. sequential scanning signals in the order of . is given, and the signal electrodes X1 to XM,
The liquid crystal display device is driven by applying a display signal in parallel to 1-X1H in synchronization with a scanning signal. For example, as shown in the drive signal waveform diagram of FIG. 5, scan signal A having the same waveform is supplied to scan electrodes Y+, YN+I, and scan electrodes Y2, YN. 2, although not shown, a scanning signal whose phase is delayed by 1/N compared to the scanning signal A is supplied, and similarly, scanning signals whose phase is delayed by 1/N are sequentially supplied to the following scanning electrodes. Then, a scanning signal B whose phase is delayed by (N-1)/N compared to the scanning signal A is supplied to the last scanning electrodes YN and YEN. On the other hand, each pixel (the intersection of the signal electrode and the scanning electrode) is arranged in the divided signal electrodes XI,
In order to turn on or off, display signals similar to the scanning signal, that is, display signals C, D, etc. having the waveforms shown in the same figure, are supplied to the other divided signal electrodes Xz, Xz' to
x. Although not shown, a display signal having a similar waveform is also supplied to +XM', and the liquid crystal display device is driven so that a voltage is applied to the intersection of each electrode.

In this way, the signal electrode X is divided into upper divided signal electrodes X+ to XM.
and lower divided signal electrodes X, r, y. It is divided into two parts, upper and lower, into divided signal electrodes XI-XM and scanning electrodes Y1~
Ys, and divided signal electrodes XI, ~X'a, and scanning electrodes Y
A liquid crystal display device in which a matrix is formed by s + I = Y 2 N, and the display is driven by sequentially applying a scanning signal to the scanning electrodes Yl-YN and YN+I-Y2N, has the following characteristics compared to a conventional matrix-structured display device: Since the so-called duty ratio, which is the ratio of the period during which each pixel is selectively operated to the total period, is improved, the number of pixels can be increased, and a liquid crystal display device with high display contrast can be obtained.

[Problem to be solved by the invention]

However, in the conventional liquid crystal display device as mentioned above,
Since the signal electrode X is divided into two into the divided signal electrode XI-XM and the divided signal electrode
Areas a, ~a where neither I8 nor scanning electrodes Y, ~Y2N are located
H exists. This area a+. ``-'aH has the disadvantage that the orientation of the liquid crystal molecules is disordered and arranged horizontally in a straight line, so it is displayed as a single display unevenness during display driving.In other words, the liquid crystal material located in the area alxa. Compared to this electric field strength, the divided signal electrodes xt, X'~
Since the electric field strength applied to the liquid crystal material differs between region a where XM + It will be displayed as a single line.

[Object of the Invention] In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to provide a liquid crystal display device that includes a large number of pixels, has high contrast, and is free from display unevenness.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a method in which a plurality of signal electrodes and a plurality of scanning electrodes that intersect with each other are arranged facing each other with a predetermined gap in between, and a liquid crystal material is applied in the gap. In a sealed liquid crystal display device, a signal electrode consisting of a divided signal electrode divided into a plurality of parts and a portion where the signal electrode is divided have a width that faces two adjacent divided signal electrodes of the divided signal electrode. The present invention is characterized by comprising: a scan electrode having a wide scan electrode; and a scan electrode driving means for selectively controlling the plurality of scan electrode groups using the wide scan electrode as the start or end of scanning.

[For production]

In the liquid crystal display device of the present invention, a wide scanning electrode that faces both of the divided signal electrodes is provided in adjacent parts of the divided signal electrode divided into a plurality of parts, so that the wide scanning electrode is provided in the divided part of the signal electrode. Since there is a wide scanning electrode, there is no significant difference in the electric field strength applied to the part where the single signal pole is separated and the other part where the scanning electrode and the signal electrode do not face each other, so display unevenness is reduced. Does not occur.

Further, since the liquid crystal display device of the present invention is equipped with a scan electrode driving means for selectively controlling the wide scan electrode as the start or end of scanning, multiplex driving is possible.
A large number of pixels can be easily driven.

〔Example〕

Examples of the present invention will be described in detail below with reference to the drawings. Explain.

As shown in FIG. 2, the liquid crystal panel 1 in the liquid crystal display device of the present invention extends in the vertical direction and is divided into upper and lower halves.
is a positive integer) signal electrodes X and 2N-
1 (N is a positive integer) scanning electrodes y are arranged facing each other with a predetermined gap so as to intersect with each other, and a liquid crystal material is sealed in the gap between these signal electrodes X and scanning electrodes y. . That is, the signal electrode X is divided into upper and lower halves, and M divided signal electrodes X, to XM are arranged upwardly in the drawing.
It is composed of M divided signal electrodes X'1 to χ'K arranged below. The scanning electrode y is connected to the upper divided signal electrode X. ”-scanning electrode yI arranged across XM
-yN-■ and the lower divided signal electrode x'x~xl
Scanning electrodes yN+t~)'2N- arranged to intersect with A
1+ and the upper divided signal electrode x. The upper and lower divided signal electrodes X+ to X, 4,
Wide scanning electrodes yN having a wide electrode width and shape are provided to intersect with '+' to X'M, respectively. That is, the scan electrode yN is connected to the other scan electrodes y,~)'
N-+. 3's++ M+-y2j1-, has a wider shape and has divided signal electrodes x1 to XA.3's++ M+-y2j1-. It intersects all of X', ~X'H, and each pixel 01 ~ C M +
At the same time as forming the divided signal electrodes X1 to d9,
It also appears in the parts e to eH where X}I and the divided signal electrode xl[~xlH are separated.

Then, the divided signal electrodes X l -XM + X'
A display signal is supplied to I~x/1 through a drive circuit to be described later, and a scan signal is supplied to scan electrodes y1 to 2N-1 via a drive circuit to be described later.

FIG. 1 is a circuit block diagram for driving the above-mentioned liquid crystal panel, and the driving circuit for the liquid crystal panel will be explained with reference to the figure. In the figure, the scanning circuit 2 is a circuit for supplying scanning signals to the scanning electrodes y1 to 3'2N-1 of the liquid crystal panel 1, and has N outputs 01 to ○H. These outputs 01 to ON are controlled by 2N-1 human power of the drive circuit 3.
1 to Izs-+. Is this connection structure as shown in the figure? , the output 01 of the scanning circuit 2 is connected to the inputs h and 128-1 of the drive circuit 3, and the output 0.
are connected to inputs I2 and 1 211-2 of drive circuit 3.

Similar connections are made up to the output ON-1 of the scanning circuit, and only the output ON of the last scanning circuit 2 is connected to one manual input IN of the drive circuit 3. That is, the scanning signal output from the output 01 of the scanning circuit 2 is input to the input 1. ，! ．． ■． The scanning signal outputted from the output 02 of the scanning circuit 2 is supplied to the input Tz, rzs of the driving circuit 3.
-z and output from the output ON of the scanning circuit 2 is supplied to the input IN of the drive circuit 3. The drive circuit 3 transfers the input scanning signal to the aforementioned scanning electrodes y1 to y2N.
-1, and output b'~
The scanning signal amplified from O' 2N-1 is sent to the scanning electrodes y1~
)'2! Output to 1-1. This output ○'l is connected to the scanning electrode y1, the output Q/2 is connected to the scanning electrode y2, and the corresponding scanning electrodes y3 to yzN-+ and the outputs Ol3 to O'2N-1 are connected in the same way. ing.

As a result, the above-mentioned amplified scanning signal is transmitted to the drive circuit 3.
The inputs ■, ~12N-1 are selected in the order in which the scan electrodes y
1~)'2N-1.

On the other hand, the image signal is sent from the terminal 4 to the single screen memories 5a and 5b.
is input to. This image signal is a signal that has already been digitized by an A/D (analog/digital) converter, etc. (not shown), and is sequentially and serially digitized into the single-sided memories 5a and 5.
Enter b. This 1-screen memory 5a has a register that can store image signals for 100 screens to be displayed on the liquid crystal panel 1, and when the image signals for 1 screen are written to this 1-screen memory 5a, the The half image signal (image data corresponding to divided signal electrodes x1 to XM) is input to the display signal generation circuit 6a, and the lower half image signal (image data corresponding to divided signal electrodes x'1 to Xl9) is input to the display signal. It is output to the generation circuit 6b.

In addition, the screen memory 5b also has a register capable of storing image signals for one screen to be displayed on the liquid crystal panel 1, and the display signal generation circuits 6a and 6b are transferred from the above-mentioned one screen memory 5a.
While the image signals are being output to the liquid crystal panel 1, image signals for the next one screen to be displayed on the liquid crystal panel 1 are written. Among the image signals written in the one-screen memory 5b, the upper half image signal is output to the display signal monitoring circuit 6a, and the lower half image signal is output to the display signal monitoring circuit 6b. Further, the display signal monitoring circuit 6a. While the image signal is being output to the memory 6b, a new image signal is written in the one-screen memory 5a.

In this way, image signals are inputted from the one-screen memories 5a and 5b to the display signal generation circuits 6a and 6b, and at this time, the display signal generation circuit 6a receives the image signals corresponding to the pixels in the upper half of the liquid crystal panel 1. Signals are input sequentially from the first scanning line to the final scanning line every scanning line, and the display signal monitoring circuit 6b receives image signals corresponding to the lower half of the image on the liquid crystal panel 1 from the final scanning line to the first scanning line. The images are manually input sequentially in the order of the scan lines. In this way, the display signal life warning circuit 6a
, 6b are input to the display circuits 6a, 6b.
Pulse width conversion and the like are performed to determine the brightness according to the image signal. Then, the image data is converted into a display signal for changing the molecular arrangement of the liquid crystal material in the liquid crystal panel 1, and is output to each liquid crystal panel l.

The display signals input from the drive circuits 7a and 7b in this way are transmitted to the aforementioned divided signal electrodes X+ -X in the liquid crystal panel 2.
H, X'1 to X' are supplied to the rivers.

In the liquid crystal display device with the structure described above, each electrode'! + ”')'zs-+r X+ ~XM I
The display signal and scanning signal supplied to X'1'''X'H and the circuit operation will be explained with reference to FIG.

In order to display an image based on an image signal on the liquid crystal panel 1, the scanning electrodes are sequentially connected according to the scanning signal output from the scanning circuit 2)'++>'2N-1→V2,)'zH-2→... →)'N-1 +)'Nyaf→YN(D
Scan electrodes are selected in this order. This scanning electrode)'+-yz
In synchronization with the selection of s-+, the display signal control circuits 6a, 6b divide the signal electrodes XI~)[MIX'I~X'
M"'Display signals are supplied in parallel. For example, the display signal G is supplied from the display signal generation circuit 6a to the divided signal electrode x., and the display signal G is supplied from the display signal generation circuit 6b to the divided signal electrode X'
, is supplied with a display signal H. As mentioned above, these display signals G and H have different pulse widths due to the difference in brightness of each pixel in the liquid crystal panel 1, and these display signals G and H have different pulse widths, for example, when scanning electrodes y+ + Vzw-I The scanning signal E supplied to the scanning signal E and the scanning signal F supplied to the scanning voltage Bi y N cause the divided signal electrode xI+ of the liquid crystal panel
A part of the image is displayed on one line corresponding to X'l. That is, in the first frame of display, the potential difference between the display signal G and each selection period of the scanning signals E, F, etc. is ■. According to the second
The pixel r+ shown in the figure. g+, etc. (intersections of divided signal electrodes X, scanning electrodes )'+,)'z, etc.) are displayed as dots
Further, the potential difference Vo between the display signal H and the scanning signals E, F, etc. during each selection period is applied to the pixel fl1, etc. (the intersection of the divided signal electrode x/direct and the scanning electrode yN.1, etc.), and a dot display is performed. .

In this way, a part of the image is displayed on one line of pixels f+, g+, f'1, etc. corresponding to the divided signal electrodes XI+X'l. Moreover, at this time, since the scanning circuit 2 and the drive circuit 3 are connected as described above, the scanning signal is transmitted to the scanning electrode Y l ”
"""l 2N-1 as described above, scanning electrode y days)
'2N-1→)'2 1)'2%-2...゛→)
"s-++ys., →'/s. In other words, the scanning signal E in FIG. 3 is supplied to the scanning electrode y1 and at the same time, it is also supplied to the scanning electrode 8ii!zw-+. , the scanning signal F is also output to the scanning TiJrlU y s
, is supplied by . Furthermore, outputs 0'2~O'N-1, O'N+I l~02 whose waveforms are not shown
The scanning electrode also corresponds to the scanning signal from N-2)'
z-yN-yN+1 to )'2N-2 are sequentially supplied.

The above-mentioned selection order of the scanning electrodes Vl-3'2N-1 is of course the same for one line corresponding to the other signal electrodes x2+χ'2, etc. Therefore, as mentioned above, the scanning electrode y1 (the upper electrode in Fig. 2) and the scanning electrode
'2N-1 (lower end electrode in FIG. 2) are sequentially selected toward the scanning electrode yH located in the middle of the liquid crystal panel 1, and by selecting the scanning electrode yN, the scanning of one screen is completed.

Therefore, by selecting scan electrodes y+-yzs-+ as described above, pixels CC2 to CM shown in FIG.
-1, d+, dz to dH-+, dM can be composed of yNl common scanning electrodes.

Moreover, this scanning electrode yN is a portion el, e2 ""e) where the signal electrode X is divided! -1 and eH, so image unevenness due to differences in electric field strength does not occur as in the conventional case.

In this embodiment, scanning electrodes y1~)'zu-+ scan (
Selection! R) order)'+ +)'2N-1→)'2
, )'2N-2→・゜゜yN force yN″y
s-+,! N◆I″゜゜・)+ , yzs−
The present invention can be implemented in the same way even if the scanning is performed in the opposite direction, such as +.

[Effects of the Invention] As described in detail above, according to the present invention, a wide scanning electrode is provided in the vertically divided portion of the signal electrode, and the wide scanning electrode faces both of the divided signal electrodes. When scanning (selecting) all the other scan electrodes included, the scan is started from this scan electrode or ends at this scan electrode, so it is possible to produce high-quality images with less display unevenness than before. Obtainable.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a matrix type liquid crystal display device of the present invention, FIG. 2 is a configuration diagram of a display panel of the present invention, and FIG. 3 is a waveform diagram of drive signals supplied to the display panel of the present invention. FIG. 4 is a configuration diagram of a conventional display panel, and FIG. 5 is a waveform diagram of the conventional display panel. ■...Liquid crystal panel, 2...Scanning circuit, 3...Drive circuit, 5a, 5b...Single screen memory, 6a, 6b...Display signal generation circuit, 7a, 7b...Drive circuit , E, F...scanning signal, G,H...display signal, X+ -Xs + X'+~x'H...divided signal electrode, yl "" yN-+ + 3' Mol~y2N-
1...Scanning electrode, yN...Wide scanning electrode. Figure 1 Figure 2

Claims (1)

[Claims] A plurality of signal electrodes and a plurality of scanning electrodes each intersect with each other,
In a liquid crystal display device in which a signal electrode is formed of a divided signal electrode divided into a plurality of parts, the signal electrode is arranged facing each other with a predetermined gap therebetween, and a liquid crystal material is sealed in the gap; a scan electrode having a wide scan electrode having a width facing both adjacent divided signal electrodes; and scan electrode driving means for selectively controlling the plurality of scan electrodes by using the wide scan electrode as a start or end of scanning. A liquid crystal display device characterized by: