JPH09244001A - Liquid crystal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal device fast in display speed and reduced in uneven picture quality. SOLUTION: An information line driving circuit 16A impressing a driving waveform corresponding to an information signal to be impressed on an information signal electrode group on pixels 9 is constituted of a first information line driver circuit 16 to be arranged at the outside of a pixel group 9 and plural second information line driving circuits 12, 13, 14 to be arranged in the internal part of the pixel group 9 and a liquid crystal panel 8 is divided into three parts by arranging the second information driving circuits 12, 13, 14 so as to divide the panel 8 in a scan direction. Then, a high-speed display is made possible and also the unevenness of display quality is made small by allowing the second information line driving circuits 12, 13, 14 to store the information signal in one scan period and transferred from the first information line driver circuit 16 in storage means and beside to output prescribed driving waveforms in prescribed timings according to the information signal with their output means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device driven by a matrix driving method, and more particularly to a liquid crystal device driven by dividing a screen.

[0002]

2. Description of the Related Art Liquid crystal devices are widely used as display devices for various OA equipment such as liquid crystal televisions and notebook computers, and a matrix driving method is known as a driving method for the liquid crystal devices. By the way, in such matrix driving, if the number of pixels of the liquid crystal panel is increased in order to display a high-definition image such as high-definition, the selection driving time per pixel becomes very short. A driver (or drive circuit) capable of high-speed driving such as 75 MHz is required.

However, since it is difficult to obtain such a high-speed driver, conventionally, a method of dividing the screen of the liquid crystal panel and driving them in parallel by using a plurality of low-speed, inexpensive, and easily-obtained drivers has been proposed. It is adopted.

Here, as such a method, for example, the display panel of the liquid crystal device is divided into a plurality of blocks in the scanning line direction, and each block is divided and driven by a driver provided in each block, There is a method for dividing and driving the liquid crystal display panel by having the information line driver of (1), preliminarily sampling the input video signal, distributing it to the plurality of drivers, and supplying in parallel as independent sampled video signals. . As a document describing a liquid crystal device adopting such a system,
Examples thereof include JP-A-59-29295 and JP-A-3-125582.

FIG. 10 is a block diagram showing an example of a display section of a liquid crystal device adopting such a driving system. In FIG. 10, 110 is an image display panel, 100 is a pixel for displaying an image of each area, and 101 is a pixel. Is a scanning line driver that selects each scanning line 102 and outputs a drive waveform to the selected scanning line 102 at a predetermined timing.

Further, 103 is an upper information line driver for outputting a predetermined drive waveform to the upper information line 104 at a predetermined timing in accordance with an image input signal of the upper screen of the image display panel 110, and 105 is a lower screen of the image display panel 110. The lower information line driver outputs a predetermined drive waveform to the lower information line 106 at a predetermined timing in accordance with a video input signal.

In the case of the screen division driving, the pixel 100 is driven according to the scanning signal added to the scanning line driver 101 and the information signals added to the information line drivers 103 and 105 provided at the upper and lower ends. I'm trying to drive.

[0008]

However, in such a conventional liquid crystal device, when each block is divided and driven, there is a problem that the screen is divided into only two because the driver is arranged in the peripheral portion of the panel. It was In the case of a method in which the information line driver is divided in the scanning line direction and the input video signals are distributed and input, there is a problem that a difference in brightness occurs between blocks due to variations in distribution characteristics and the image quality is impaired. It was

Further, according to this method, in the case of simple matrix driving, the speedup by dividing the screen can be gained only for the storage time of the information signal, and this time is very short with respect to the scanning time, so that the display speed cannot be achieved so much. There were also problems.

Therefore, the present invention has been made in order to solve such a problem, and an object of the present invention is to provide a liquid crystal device having a high display speed and little image quality unevenness.

[0011]

SUMMARY OF THE INVENTION The present invention is a liquid crystal device for displaying an image by driving a large number of pixels constituting a liquid crystal panel by information signals and scanning signals applied to an information signal electrode group and a scanning signal electrode group. In the first information, the information line drive circuit for applying a drive waveform according to the information signal applied to the information signal electrode group to the pixel is provided, and the information line drive circuit is arranged outside the pixel group. It is characterized by comprising a line drive circuit and a plurality of second information line drive circuits arranged inside the pixel group.

Further, the present invention is characterized in that the second information line driving circuit is arranged so as to divide the liquid crystal panel in the scanning direction.

Further, the invention is characterized in that the liquid crystal panel is divided into at least three by the plurality of second information line driving circuits.

Further, according to the present invention, the first information line drive circuit includes a transfer means for transferring an information signal of one scanning period to the second information line drive circuit and a control means for controlling a transfer operation of the transfer means. The second information line drive circuit includes storage means for accumulating the information signal from the transfer means and output means for outputting a predetermined drive waveform at a predetermined timing according to the information signal of the storage means. It is a feature.

The present invention is also characterized in that the transfer means is a shift register.

Further, the present invention is characterized in that the shift register transfers an information signal serially input to each of the second information line drive circuits in parallel.

Further, the present invention is characterized in that the first information line drive circuit and each of the second information line drive circuits are connected by one information line.

Further, the present invention is characterized in that the information signal electrode group and the scanning signal electrode group are formed in a matrix.

The present invention is also characterized in that the liquid crystal used in the liquid crystal panel is a ferroelectric liquid crystal.

Further, the invention is characterized in that the ferroelectric liquid crystal used in the liquid crystal panel is a chiral smectic liquid crystal.

Further, the information line drive circuit for applying the drive waveform corresponding to the information signal applied to the information signal electrode group to the pixel in this way is the first information line drive circuit arranged outside the pixel group. , A plurality of second information line driving circuits arranged inside the pixel group, and by arranging the second information line driving circuits so as to divide the liquid crystal panel in the scanning direction, at least three liquid crystal panels are provided. To divide. Then, the second information line drive circuit accumulates the information signal of one scanning period transferred from the transfer means in the storage means under the control of the control circuit of the first information line drive circuit, while the output means predetermined the predetermined information signal according to the information signal. By outputting a predetermined drive waveform at the timing of, high-speed display is possible.

Further, by connecting the first information line driving circuit and each of the second information line driving circuits with one information line,
Make the structure simple.

Furthermore, by using a chiral smectic liquid crystal which is a ferroelectric liquid crystal as the liquid crystal used in the liquid crystal panel, the material itself can be made to operate at a higher speed and display at a higher speed is possible.

[0024]

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

FIG. 1 is a block diagram of a liquid crystal device according to an embodiment of the present invention. In the figure, reference numeral 1 is a graphic controller, and data transmitted from the graphic controller is input to a scanning signal control circuit 3 and an information signal control circuit 4 through a drive control circuit 2 and converted into scanning line address data and display data, respectively. After that, it is input to the scanning signal applying circuit 5 and the information signal applying circuit 7.

Then, the scanning signal applying circuit 5 to which the scanning line address data is input generates a scanning selection signal and a scanning non-selection signal in accordance with the scanning line address data,
The voltage is applied to the scanning signal electrode group of the liquid crystal display unit 6 via the scanning line driver described later. The information signal application circuit 7 to which the display data is input generates an information signal according to the display data and applies it to the information signal electrode group of the liquid crystal display unit 6 via the information line main and information line auxiliary drivers described later. I am trying.

By the way, the graphic controller 1
Generates a scanning system signal and sends it to the drive control circuit 2. Based on this scanning system signal, the drive control circuit 2 selects a drive waveform according to the scanning system, and outputs it to the scanning signal control circuit 3. The waveform data is sent to the scanning signal applying circuit 5 and the information signal applying circuit 7 through the information signal control circuit 4.

On the other hand, FIG. 2 is a diagram showing the structure of the liquid crystal display unit 6, in which 8 is a liquid crystal panel (display panel), 9 is a large number of pixels constituting the liquid crystal panel 8, and 10 is each scanning line. A scanning line driver that selects 11 and outputs a driving waveform to the selected scanning line 11 at a predetermined timing, 1
2, 13 and 14 are arranged inside the pixel group 9 and the information line 15
The first, second and third auxiliary information line drivers, which are a plurality of second information line driving circuits for applying a driving waveform to the pixel 9 through In the present embodiment, these auxiliary information line drivers 12, 13, 14 are provided in three pieces so as to divide the screen of the liquid crystal panel 8 into three in the scanning line 11 direction.

The first information 16 is arranged outside the pixel group 9 and supplies an information signal to the auxiliary information line drivers 12, 13 and 14 at a predetermined timing through the auxiliary driver connection line 17 in accordance with a video input signal. This is an information line main driver which is a line drive circuit, and in the present embodiment, the information line main driver 16 has three scanning lines (first scanning line of each divided screen) input via the information signal applying circuit 7. Is supplied to the auxiliary information line drivers 12, 13, and 14. The information line main driver 16 and the auxiliary information line drivers 12, 13, and 14 form an information line drive circuit 16A that applies a drive waveform corresponding to the information signal applied to the information signal electrode group to the pixel 9. It

FIG. 3 is a partial cross-sectional view of the liquid crystal panel 8. In FIG. 3, 81 and 82 are glass substrates which are a pair of substrates having a thickness of 1.1 mm and which are opposed to each other. Transparent electrodes 83 and 84 forming the information signal electrode group and the scanning signal electrode group are formed on 81 and 82. Further, 85 and 86 are alignment control films, and 87 is a liquid crystal filled between the glass substrates 81 and 82.

By the way, in FIG. 4, such an information line main driver 16 and each auxiliary information line driver 12, 13, 14 are shown.
FIG. 3 is a diagram showing a flow of an information signal between the information signal applying circuit 7 and the information signal Si for three scanning lines.
To the auxiliary information line driver 1 according to the screen information signal S1 from the screen selection circuit 16b.
A line memory 12a, which is a storage means of 2, 13, 14;
The data is transferred in parallel to 13a and 14a and accumulated.

Further, the line memories 12a, 13a,
The information signal Si accumulated in 14a is a predetermined drive waveform amplified on a predetermined timing by the segment drivers 12b, 13b, 14b, which are output means of the auxiliary information line drivers 12, 13, 14 and on each scanning line 11. Pixel 9
While being supplied to the scan line 1 by the scan line driver 10.
When a scan selection signal is supplied through 1, the pixels 9 are applied to drive the pixels 9. In the figure, 16c is a display controller which is a control means for controlling the transfer operation of the shift register 16a and the screen selection circuit 16b.

Then, in this way, the information line main driver 16
The information signals Si for three lines input to the auxiliary information line drivers 12, 13, 14 are input to the shift register 16a.
By transferring the data in parallel to, the screens of the liquid crystal panel 8 divided into three can be simultaneously driven, so that high-speed display is possible. In addition, by transferring the information signal Si in parallel to the auxiliary information line drivers 12, 13, and 14 in this way, variations in distribution characteristics are eliminated, and uneven image quality is reduced.

Next, the display operation of the liquid crystal device having such a configuration will be described.

First, an information signal Si for three scanning lines corresponding to a video input signal is serially input to the shift register 16a of the information line main driver 16 shown in FIG. FIG.
Shows the state where the information signals for three scanning lines are input to the information line main driver 16 in this way.

Next, in response to the screen information signal S1 from the screen selection circuit 16b, the 3 input to the information line main driver 16
The information signals of the scanning lines are parallel to the first, second and third auxiliary information line drivers 1 as shown in FIGS. 6, 7 and 8.
2, 13, 14 line memories 12a, 13a, 14a
Are transferred to and accumulated.

Then, after the information signals of the scanning lines of the divided screen are accumulated in the auxiliary information line drivers 12, 13, 14 in this way, the segment drivers 12b, 13b, 14 are formed.
When a scanning signal is supplied to the pixel 9 on each scanning line 11 as a predetermined driving waveform amplified by b at a predetermined timing, and a scanning signal is supplied from the scanning line driver 1 through the scanning line 11 in synchronism therewith, those scannings are performed. A predetermined drive waveform is applied to the pixels 9 in the line, and those pixels 9 are driven as shown in FIG. At this time, the signal of the next scanning line is supplied to and accumulated in the information line main driver 16 as shown in FIG.

As described above, according to the screen division driving method of the present embodiment, an arbitrary number of division drives can be performed in the scanning line direction, and high-speed display can be performed accordingly.

The liquid crystal panel 8 has been described above.
Although the case where the screen is divided into three has been described, the present invention is not limited to this, and the pixel 9 may be divided into any number in the scanning line direction. And, no matter how many divisions are made in this way, the wiring is the information line 4 and the auxiliary driver connection line 17
Since it can be configured with only two of them, it is easy to create.

On the other hand, in the present invention, the liquid crystal used in the liquid crystal panel generally has a non-helical chiral smectic C phase (SmC ^* ) or chiral smectic H phase (SmH ^* ) in a specific temperature range. In the state, one of the first optical stable state and the second optical stable state corresponding to the applied electric field, and the property of maintaining that state when no electric field is applied, that is, bistability A ferroelectric liquid crystal having, for example, a chiral smectic liquid crystal is used.

Since such a ferroelectric liquid crystal responds quickly to changes in the electric field, by using the ferroelectric liquid crystal as described above, the speed of the liquid crystal material itself can be increased and the speed can be increased. It becomes possible to display.

[0042]

As described above, according to the present invention, the second information line drive circuit of the information line drive circuit for applying the drive waveform corresponding to the information signal to the pixel is arranged inside the pixel group, It is possible to drive an arbitrary number of divisions. In addition, by transferring the information signal in parallel from the first information line drive circuit arranged outside the pixel group to each second information line drive circuit and outputting it as a predetermined drive waveform at a predetermined timing, high-speed display is achieved. It is possible to reduce the image quality unevenness.

Further, by using the ferroelectric liquid crystal for the liquid crystal panel, the speed of the material itself can be increased, and higher speed display can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram of a liquid crystal device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a liquid crystal display unit of the liquid crystal device.

FIG. 3 is a partial cross-sectional view of a liquid crystal panel of the liquid crystal display unit.

FIG. 4 is a diagram showing the flow of information signals between the information line main driver and the first, second and third auxiliary information line drivers of the liquid crystal display section.

FIG. 5 is a diagram showing a state in which information signals for three scanning lines are input to the information line main driver.

FIG. 6 is a diagram showing a state in which an information signal for one scanning line is transferred to the first auxiliary information line driver.

FIG. 7 is a diagram showing a state in which an information signal for one scanning line is transferred to the second auxiliary information line driver.

FIG. 8 is a diagram showing a state in which an information signal for one scanning line is transferred to the third auxiliary information line driver.

FIG. 9 is a diagram showing how pixels are driven.

FIG. 10 is a diagram showing a configuration of a liquid crystal display unit of a liquid crystal device of a conventional liquid crystal device.

[Explanation of symbols]

 6 liquid crystal display section 7 information signal application circuit 8 display panel 9 pixel 10 scanning line driver 12, 13, 14 auxiliary information line driver 12a, 13a, 14a line memory 12b, 13b, 14b segment driver 16 information line main driver 16a shift register 16c Display controller 16A Information line drive circuit 87 Liquid crystal Si information signal

Claims (10)

[Claims] 1. A liquid crystal device for displaying an image by driving a large number of pixels constituting a liquid crystal panel by an information signal and a scanning signal applied to the information signal electrode group and the scanning signal electrode group. An information line drive circuit for applying a drive waveform according to an applied information signal to the pixel is provided, and the information line drive circuit is arranged outside the pixel group.
A liquid crystal device comprising an information line drive circuit and a plurality of second information line drive circuits arranged inside the pixel group. 2. The liquid crystal device according to claim 1, wherein the second information line drive circuit is arranged so as to divide the liquid crystal panel in a scanning direction. 3. The liquid crystal device according to claim 1, wherein the liquid crystal panel is divided into at least three by the plurality of second information line driving circuits. 4. The first information line drive circuit comprises a transfer means for transferring an information signal of one scanning period to the second information line drive circuit, and a control means for controlling a transfer operation of the transfer means. The second information line drive circuit is provided with storage means for accumulating the information signal from the transfer means and output means for outputting a predetermined drive waveform at a predetermined timing according to the information signal of the storage means. The liquid crystal device according to claim 1. 5. The liquid crystal device according to claim 1, wherein the transfer means is a shift register. 6. The liquid crystal device according to claim 1, wherein the shift register transfers an information signal serially input to each of the second information line driving circuits in parallel. 7. The liquid crystal device according to claim 1, wherein the first information line drive circuit and each of the second information line drive circuits are connected by one information line. 8. The liquid crystal device according to claim 1, wherein the information signal electrode group and the scanning signal electrode group are formed in a matrix. 9. The liquid crystal device according to claim 1, wherein the liquid crystal used in the liquid crystal panel is a ferroelectric liquid crystal. 10. The liquid crystal device according to claim 1, wherein the ferroelectric liquid crystal used in the liquid crystal panel is a chiral smectic liquid crystal.