JPH09190162A - Method and circuit for driving matrix display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a flicker by using through mixing a simultaneous scanning system of two lines with a point inversion system. SOLUTION: A gate device circuit drives simultaneously one of odd numbered gate lines and one of even numbered gate lines in a bundle through two registers 1, 2 individually driving the odd numbered gate lines and the even numbered gate lines. In the odd numbered field of a two line simultaneous drive system, two gate lines such as NO.1, 2 gate lines, NO.3, 4 gate lines are bundled into one unit, and a signal is imparted successively, and in the even numbered field, two gate lines such as NO.1 gate line, NO.2, 3 gate lines, NO.4, 5 gate lines are bundled into one unit, and the signal is imparted successively. Then, when a certain bundle of gate lines is opened, upper part and lower part data drive circuits 10, 20 send out the signals with polarities opposite to each other, and when a next gate line bundle is opened, the upper part and lower part data drive circuits 10, 20 send out signals with the polarities of respective signals inverted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method and a driving circuit of a matrix type display device, and more specifically, a driving method in which two lines are simultaneously scanned and a point inversion method is mixed, and a driving method thereof. Drive circuit for.

[0002]

2. Description of the Related Art A liquid crystal display device (LCD: liquid crystal) is one of the alternatives to the conventional cathode ray tube (CRT), which is heavy and consumes a large amount of power and is mainly used as a display device such as a computer monitor. display, plasma display panel (PDP), electroluminescence (EL), field emission display (FED), and other flat panel displays (FPD). For such a flat panel display device or the like, a matrix type wiring structure is used in which the horizontal and vertical directions are orthogonal to each other.

A liquid crystal display device is a typical matrix type flat panel display device that is easy to carry. Among them, an active matrix liquid crystal display device using a thin film transistor as a switching element is mainly used. . Most of the thin film transistors use non-liquid silicon, but thin film transistors using polycrystalline silicon, which has high mobility and high integration, are in the spotlight.

Now, a driving method of a conventional polycrystalline silicon thin film transistor liquid crystal display device will be described in detail with reference to FIGS. First, a wiring structure and a driving circuit of a conventional polycrystalline silicon thin film transistor liquid crystal display device will be considered with reference to FIG. A large number of data lines (G
₁ , G ₂ , ..., G _m , G _{m + 1} , ...) are formed and connected to the gate drive circuit, and a large number of data lines (D ₁ , D _2, ······, it is coupled to the D _n · · · · · ·) are formed by the data driving circuit.

A method of applying data to each pixel in such a liquid crystal display device is as follows. First, the first transistor of the pixel gate lines (G ₁₎ switching signal is coupled to a first gate line when it is applied (G ₁₎ is turned on. Data lines (D ₁ , D ₂ , ..., D _n ...) Through the turned-on transistors.
The image signal applied from is applied to the pixel.

Then, the switching signal applied to the _first gate line (G ₁ ) is cut off and the switching signal is applied to the second gate line (G ₂ ). Then, the transistor connected to the _first gate line (G ₁ ) is turned off, the transistor connected to the second gate line (G ₂ ) is turned on, and the image signal is applied. At this time, the applied signal is generally opposite in polarity to the data signal applied in the preceding row.

When the switching signal is sequentially scanned up to the gate line in this manner, scanning is started again from the first gate line (G ₁ ). At this time, it is general to apply a signal having a polarity opposite to that of the previous period to the image signal of the next period.

[0008]

However, as the integration degree increases, the number of data lines increases, which makes the scanning method different from the conventional one, that is, the double scan method or the two-line simultaneous scanning method. two line simultaneous scan)
The method is newly used. The double scanning method is a method of forming a screen by doubling the frequency of the image signal as compared with the conventional method, and the image processing for the double scanning is separately required, which increases the cost. In addition, since the data sampling frequency of the data driving circuit is increased, the time for data to be used for one gate line is reduced, so that the image quality is hardly improved. Absent.

The two-line simultaneous scanning system is a system for driving two gate lines at the same time. For example, two gate lines such as 1.2 gate lines and 3.4 gate lines are bundled and driven at the same time. Although it is easy, there is a problem that the vertical resolution is reduced. A conventional method for overcoming the problem of the two-line simultaneous scanning method is shown in FIGS.
Will be explained with reference to.

In this method, a scan frame corresponding to a time twice the scan cycle is divided into an odd field and an even field. When the scan field is an odd field, as shown in FIG. When scanning is performed simultaneously by bundling in 3 and 4 gate lines, etc.
As in (B), 1 gate line, 2.3 gate line, 4.5
Scan them at the same time by bundling them in a gate line.

Since the image signal is continuously inverted and input in this method, the polarity of the image signal applied to each pixel matrix is the same as that shown in FIG. 3A in the odd field of the first frame. In this case, the polarity in the even field of the same frame is as shown in FIG. 3 (B), the polarity in the odd field of the second frame is FIG. 3 (C), and the polarity in the even field is also FIG. 3 (D). The polarity in the odd field of the third frame is as shown in FIG.

However, in the case of such a system, although the resolution in the odd number direction is increased, the polarity of the image signal of each gate line is changed by changing the field. As an example, looking at the polarity change of the data line input to the first column in FIGS. 3A to 3E, (+), (+), (−),
Change to (-), (+), etc. Therefore, there is a problem that 15 Hz flicker occurs and the image quality deteriorates.

An object of the present invention is to solve these problems, and a dot inversion (dot inv) method is adopted in the two-line simultaneous scanning method.
ersion) method to try to prevent the 15Hz flicker phenomenon.

[0014]

A driving method of a matrix type display device according to the present invention performs a display operation by a signal applied through a large number of horizontal signal lines and a large number of vertical signal lines, and The horizontal signal line is divided into a large number of horizontal signal line bundles including two or more horizontal signal lines, and a switching signal is simultaneously applied to one horizontal signal line bundle.
Dividing into a large number of vertical signal line bundles including one or more vertical signal line and applying image signals having different polarities to adjacent vertical signal line bundles.

Here, it is preferable that the horizontal signal line bundle includes two horizontal signal lines adjacent to each other, and the vertical signal line bundle can be configured by one vertical signal line or three vertical signal lines adjacent to each other. In addition, the configuration can further include a step of applying a switching signal to another horizontal signal line bundle among a large number of horizontal signal line bundles, and a step of applying an image signal whose polarity is inverted to the vertical signal line bundle.

Further, according to the present invention, there is provided a driving method of a matrix type display device which performs a display operation by a signal applied through a large number of horizontal signal lines and a large number of vertical signal lines. Dividing into a large number of horizontal signal line bundles each consisting of one horizontal signal line, applying a switching signal to the horizontal signal line bundles in order, and dividing a large number of vertical signal lines into a large number of vertical signal line bundles including one or more vertical signal lines. And a step of applying image signals having different polarities to adjacent vertical signal line bundles each time a switching signal is applied, the method of driving the matrix type display device.

Here, the vertical signal line bundle is one vertical signal line,
Alternatively, it can be configured by three adjacent vertical signal lines. It is also preferable to apply an image signal whose polarity is inverted to the vertical signal line bundle each time the horizontal signal line bundle to which the switching signal is applied changes. Further, one frame to be displayed includes a first field and a second field, and the first field applies a switching signal to a large number of horizontal signal line bundles composed of two adjacent horizontal signal lines.
The second field follows after the switching signals have been applied to all the horizontal signal line bundles once in the first field, and two adjacent horizontal lines shifted by one from the horizontal signal line bundle in the first field. A switching signal may be sequentially applied to a large number of horizontal signal line bundles formed of signal lines, and image signals having different polarities may be applied to adjacent vertical signal line bundles each time the switching signal is applied.

If the polarity of the image signal is not inverted between the corresponding pixels of the first field and the second field in the same frame, and one frame consisting of the first field and the second field is completed, It is preferable to invert the polarity of the image signal and apply it to the vertical signal line bundle. Further, the driving circuit of the matrix type display device according to the present invention includes a large number of pixels arranged in a matrix, and a switching signal and an image signal applied through a large number of horizontal signal lines and a large number of vertical signal lines. A driving circuit of a matrix type display device which performs a display operation, wherein a first shift register for outputting a switching signal to an odd-numbered horizontal signal line among the horizontal signal lines and an even-numbered horizontal signal line among the horizontal signal lines An open / close signal drive circuit including a second shift register that outputs a switching signal to the first and second image signal drive circuits that output image signals to odd-numbered vertical signal lines in the vertical signal lines and an even number in the vertical signal lines. And a second image signal drive circuit for outputting an image signal to the th vertical signal line.

Further, according to the present invention, the switching signal is output to the first shift register for outputting the switching signal to the odd-numbered horizontal signal lines among the horizontal signal lines and the even-numbered horizontal signal line for the horizontal signal lines. The switching signal drive circuit including the second shift register and the adjacent three in the vertical signal line
A first image signal drive circuit that bundles two vertical signal lines into a bundle and outputs an image signal to an odd-numbered vertical signal line bundle, and a second image signal that outputs an image signal to an even-numbered vertical signal line bundle among the vertical signal line bundles A configuration including an image signal drive circuit is disclosed.

Here, the first and second image signal drive circuits may be configured to include means for simultaneously applying signals to the vertical signal lines in one vertical signal line bundle, and the signal applying means may be a shift register and a shift register. , And a large number of signal opening / closing means for opening / closing an image signal entering the vertical signal line in response to a signal from the shift register. Further, here, the signal opening / closing means is a pulse generator connected to the shift register,
An output terminal may be connected to the vertical signal line, an image signal may be applied to the input terminal, and both control terminals may include a number of transmission gates connected to a pulse generator.

When the matrix type display device is driven by such a method and device, flicker can be prevented because signals whose polarities are inverted depending on the rows and columns of the pixels are input.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display device to which an embodiment of the present invention is applied will be described in detail with reference to the accompanying drawings. FIG. 4 is a sectional view illustrating a gate driving circuit according to a first embodiment of the present invention, wherein the gate driving circuit includes two shift registers (1 and 2) for individually driving an odd gate line and an even gate line. . These two shift registers (1,
Through 2), one of the odd gate lines and one of the even gate lines can be bundled and driven simultaneously.

FIG. 5 is a sectional view showing a data driving circuit according to the first embodiment of the present invention. The data driving circuit is an upper data driving circuit formed on the top of the panel.
(10) and a lower data driving circuit (20) formed at the bottom of the panel, and each data line is alternately connected to the upper and lower data driving circuits (10, 20). Next, a driving method of the liquid crystal display device according to the embodiment of the present invention will be described in detail with reference to FIGS. 6 and 7. FIG.
(A) is a timing diagram of a switching signal in the case of an odd field, FIG. 6 (B) is a timing diagram of a switching signal in the case of an even field, and FIG. 7 (A) is sent from the upper data drive circuit (10). FIG. 7B is a timing chart of the image signal, and FIG. 7B is a timing chart of the image signal sent from the lower data drive circuit 20.

First, in the case of an odd field of the 2-line simultaneous drive system, as shown in FIG. 6A, two gate lines such as a 1.2 gate line and a 3.4 gate line are bundled into one unit. 6B, signals are applied in sequence, and when an even field, as shown in FIG. 6B, two gate lines such as 1 gate line, 2.3 gate line, and 4.5 gate line are bundled into one unit in order. Apply a signal.

Next, when a bundle of gate lines is opened, the upper data driving circuit 10 and the lower data driving circuit 20 output signals having polarities opposite to each other, and when the next gate line bundle is opened, the upper data driving circuit 10 and the lower data driving circuit 20 are opened. The lower data drive circuits (10) and (20) invert the polarities of the signals and send them out. To give an example, see FIG.
As shown in (A) and (B), when one gate line bundle is opened, if an image signal of (+) polarity is applied to the upper data driving circuit (10), the lower data driving circuit (20) When a signal of (-) polarity is displayed and the next gate line bundle opens, the upper data drive circuit (10) reverses (-)
When a polarity image signal is applied, the lower data driving circuit sends out a (+) polarity signal.

In this case, the two polarities alternately appear in one row and the polarities change every two columns in the column direction. In addition, the polarity of the image signal is not inverted depending on the field within the same frame, and the polarity of the image signal is inverted when the frame changes. For example, if an image signal of (+) polarity is applied to the pixel row of the Nth bundle in the odd field of one frame, it is applied to the pixel row of the Nth bundle in the even field of the frame. An image signal of (+) polarity is applied. However, in the odd field and the even field of the next frame, the signal of the (-) polarity is applied to the pixel row of the Nth bundle.

FIG. 8 is a diagram showing this, and (A)
Represents the polarity of the image signal in the odd field of the first frame, (B) is the even field of the first frame, (C) is the odd field of the second frame,
(D) is an even field of the third frame, (E) is 3
It shows the polarity in the even field of the second frame.

As can be seen here, the polarities of the image signals appear alternately in one row within the same field, and the polarities change every two columns in the column direction. In the same frame, the same polarity appears for the pixel row bundles in the same order in the odd field and the even field.
However, when the frame changes, even the pixel row bundles in the same order have opposite polarities.

As a result, signals of opposite polarities are applied to the pixels of adjacent pixel columns, so that flicker is reduced. Next, a method of driving the polycrystalline silicon thin film transistor liquid crystal display device according to the second embodiment of the present invention will be described in detail with reference to FIG. The gate drive circuit according to the present embodiment is the same as that of the first embodiment shown in FIG.

Further, the data drive circuit according to the present embodiment has a structure slightly different from that of the first embodiment. That is, as shown in FIG. 9, the upper data driving circuit 10 formed on the panel is a shift register 11 and a plurality of pulse generators 12 and 12 connected to the shift register 11. A number of transmission gates (T
G) is included. Similarly, the lower data driving circuit (20) formed at the bottom of the panel is connected to the shift register (21), a plurality of pulse generators (22) and (22) connected to the shift register (21). Multiple transmission gates (T
G) is included.

In the present embodiment, the three data lines form one bundle, and each bundle is alternately connected to the upper and lower data driving circuits (10, 20). This will be described in more detail. Each data line is connected to the output terminal of a transmission gate (TG1, TG2, TG3) to which a P-type MOS transistor and an N-type MOS transistor are connected. 1
3 connected to each of the 3 data lines contained in the bundle
The control terminals of one transmission gate (TG1, TG2, TG3) are connected in parallel to one pulse generator (12), (22), respectively.

In addition, transmission gates (TG1, TG
2 、 TG3) input terminals are 3 signal lines that send out image signals
(R, G, B) respectively. In this embodiment having such a structure, basically the same driving method as that in the first embodiment is selected, but unlike the first embodiment, three data lines are bundled and simultaneously output. Since the structure is selected, the time for applying the image signal is increased to 3 times as compared with the first embodiment.

A pulse generator (12) produces appropriate signals for opening and closing transmission gates (TG1, TG2, TG3) from the output of the shift register (11) to apply signals to three data lines simultaneously. This signal causes three transmission gates (TG1, TG2, TG3) connected to one pulse generator (12) to become conductive or non-conductive at the same time,
While the transmission gates (TG1, TG2, TG3) are open, 3 signals from each of the 3 signal lines (R, G, B)
Input to one data line.

Here, the reason why the three data lines are made into one bundle is to drive the three basic shades of red, green, and blue, which are the basic shades for color display, into one bundle. The polarities appearing in this embodiment are the same as those appearing in FIGS. 8 (A) to 8 (E). However, in FIG. 8 (A) to (E), 1
It should be noted that what is displayed by one pixel corresponds to three pixels in this embodiment.

[0035]

As described above, in the matrix type display device according to the present invention, by using the two-line simultaneous scanning method and the point inversion method in a mixed manner, it is possible to prevent the occurrence of flicker which is caused by the conventional two-line simultaneous scanning method. .

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a driving circuit of a conventional matrix type display device.

2A and 2B are timing charts of switching signals used in a driving method of a conventional matrix display device, FIG. 2A is a timing chart in an odd field, and FIG. 2B is a timing chart in an even field.

FIG. 3 is a diagram illustrating, for each pixel, a polarity of an image signal that appears in a conventional method of driving a matrix display device.

FIG. 4 is a sectional view illustrating a gate driving circuit according to a first exemplary embodiment of the present invention.

FIG. 5 is a sectional view illustrating a data driving circuit according to the first exemplary embodiment of the present invention.

FIG. 6 is a timing diagram of a switching signal according to an exemplary embodiment of the present invention, (A) is a timing diagram when an odd field, and (B) is a timing diagram when an even field.

FIG. 7 is a timing diagram of a switching signal according to an embodiment of the present invention, (A) is a timing diagram of an image signal sent from an upper data driving circuit, and (B) is a timing diagram of an image signal sent from a lower data driving circuit. It is a timing diagram.

FIG. 8 is a diagram illustrating, for each pixel, the polarity of an image signal that appears in the driving method of the matrix display device according to the present invention.

FIG. 9 is a circuit diagram illustrating a data driving circuit according to a second exemplary embodiment of the present invention.

[Explanation of symbols]

 1, 2, 11, 21: shift register 10, 20: drive circuit 12, 22: pulse generator G1, G2: gate line TG1, TG2, TG3: transmission gate

Claims (20)

[Claims] 1. A driving method of a matrix type display device for performing a display operation by a signal applied through a large number of horizontal signal lines and a large number of vertical signal lines, wherein the large number of horizontal signal lines are two or more horizontal signals. Dividing a plurality of horizontal signal line bundles including lines to apply a switching signal to the one horizontal signal line bundle at the same time, and dividing the plurality of vertical signal lines into a plurality of vertical signal line bundles including one or more vertical signal lines. And applying image signals having different polarities to the adjacent vertical signal line bundles. 2. The method for driving a matrix type display device according to claim 1, wherein the horizontal signal line bundle includes two horizontal signal lines. 3. The method for driving a matrix type display device according to claim 1, wherein the horizontal signal lines included in the horizontal signal line bundle are adjacent to each other. 4. The driving method for a matrix type display device according to claim 1, wherein the vertical signal line bundle includes one vertical signal line. 5. The method for driving a matrix type display device according to claim 1, wherein the vertical signal lines included in the vertical signal line bundle are adjacent to each other. 6. The method of driving a matrix display device according to claim 4, wherein the number of the vertical signal lines in the vertical signal line bundle is three. 7. The method further comprising: applying a switching signal to another horizontal signal line bundle among the plurality of horizontal signal line bundles; and applying an image signal whose polarity is inverted to the vertical signal line bundle. 7. A method for driving a matrix type display device according to any one of 1 to 6. 8. A driving method of a matrix type display device for performing a display operation by a signal applied through a large number of horizontal signal lines and a large number of vertical signal lines, wherein the plurality of horizontal signal lines are adjacent to each other. Dividing the horizontal signal line bundle into a plurality of horizontal signal line bundles and sequentially applying a switching signal to the horizontal signal line bundle; dividing the plurality of vertical signal lines into a plurality of vertical signal line bundles including one or more vertical signal lines. And applying image signals having different polarities to the adjacent vertical signal line bundles each time the switching signal is applied, the driving method of the matrix type display device. 9. The driving method of a matrix type display device according to claim 8, wherein the vertical signal line bundle is composed of one vertical signal line. 10. The method of driving a matrix display device according to claim 8, wherein the vertical signal lines included in the vertical signal line bundle are adjacent to each other. 11. The method of driving a matrix display device according to claim 10, wherein the number of vertical signal lines included in the vertical signal line bundle is three. 12. The matrix type according to claim 8, wherein an image signal whose polarity is inverted is applied to the vertical signal line bundle each time the horizontal signal line bundle to which the switching signal is applied changes. Driving method of display device. 13. One frame displayed on the matrix type display device includes a first field for applying a switching signal to a large number of horizontal signal line bundles composed of two adjacent horizontal signal lines, and all of the first field. A horizontal signal line bundle is applied with a switching signal once after each, and the horizontal signal line bundle is followed by a large number of horizontal signal lines which are shifted from the horizontal signal line bundle in the first field by one. 9. The matrix type display device according to claim 8, further comprising: a second field in which switching signals are sequentially applied to the line bundles and image signals having different polarities are applied to adjacent vertical signal line bundles each time the switching signal is applied. Driving method. 14. The method for driving a matrix type display device according to claim 13, wherein the polarities of the image signals are not inverted between corresponding pixels in the first field and the second field in the same frame. 15. The matrix type display according to claim 14, wherein, when one frame including the first field and the second field is completed, the polarity of the image signal is inverted and applied to the vertical signal line bundle. Device driving method. 16. A driving method of a matrix type display device, comprising a plurality of pixels arranged in a matrix, and performing a display operation by a switching signal and an image signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines. A first shift register for outputting a switching signal to an odd-numbered horizontal signal line of the horizontal signal lines and a second shift register for outputting a switching signal to an even-numbered horizontal signal line of the horizontal signal lines. A switching signal drive circuit including a shift register, a first image signal drive circuit that outputs an image signal to an odd-numbered vertical signal line among the vertical signal lines, and an even-numbered vertical signal among the vertical signal lines A drive circuit of a matrix type display device including a second image signal drive circuit which outputs an image signal to a line. 17. A driving method of a matrix type display device, comprising a plurality of pixels arranged in a matrix, and performing a display operation by a switching signal and an image signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines. A first shift register outputting a switching signal to an odd-numbered horizontal signal line among the horizontal signal lines and a first shift register outputting a switching signal to an even-numbered horizontal signal line among the horizontal signal lines A switching signal drive circuit including two shift registers, and a first image signal drive that bundles three adjacent vertical signal lines among the vertical signal lines into a bundle and outputs an image signal to an odd-numbered vertical signal line bundle among them. A drive circuit for a matrix type display device, comprising: a circuit; and a second image signal drive circuit that outputs an image signal to an even-numbered vertical signal line bundle in the vertical signal line bundle. 18. The matrix type display device according to claim 17, wherein the first and second image signal driving circuits include signal applying means for simultaneously applying signals to vertical signal lines included in one vertical signal line bundle. Drive circuit. 19. The matrix type display according to claim 18, wherein the signal applying means includes a shift register and a plurality of signal opening / closing means for opening / closing an image signal entering the vertical signal line by a signal from the shift register. Device drive circuit. 20. The signal opening / closing means includes a pulse generator connected to the shift register,
20. The matrix according to claim 19, wherein an output terminal is connected to the vertical signal line, an image signal is applied to the input terminal, and both control terminals include a plurality of transmission gates connected to the pulse generator. Type display device drive circuit.