JP2982877B2 - Active matrix liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active matrix liquid crystal display in which switching elements for driving are respectively connected to individual pixel electrodes.

[0002]

2. Description of the Related Art FIG. 4 is a plan view of a conventional liquid crystal display device of this kind. As shown in FIG. 1, a conventional active matrix liquid crystal display device includes scan electrodes X _{1 to} X _n provided in parallel with each other, and signal electrodes Y _{1 to} Y _m provided orthogonal to the scan electrodes. It was composed of a pixel electrode 1 provided in a region surrounded by each electrode, and a thin film transistor (hereinafter, referred to as TFT) 2 for driving the pixel electrode 1.

The driving method of this liquid crystal display device is roughly divided into the following three methods. Frame while the inversion mode scanning electrodes are selected from X ₁ to X _n, the signal electrodes Y ₁ to Y _m is added a constant polarity signal, a method of polarity inversion of the signal in the next frame. FIG. 5 shows the polarity of the voltage applied to the liquid crystal when driven by this method.

[0004] When the gate-line inversion method scan electrodes X ₁ is selected, the particular polarity signals applied to all the signal electrodes Y ₁ to Y _m, the signal when the scanning electrode X ₂ is selected And the polarity of the signal of the signal electrode is inverted each time the selection of the scanning electrode changes. FIG. 6 shows the polarity of the voltage applied to the liquid crystal of each pixel during driving by this method. This polarity is inverted when the next frame is driven.

Drain / line inversion type scanning electrode X ₁
A method in which a signal voltage whose polarity is inverted is applied to the signal electrodes Y _{1 to} Y _m for each signal electrode while the signals X to X _n are selected.
FIG. 7 shows the polarity of the voltage applied to the liquid crystal when driven by this method. The polarity shown is reversed in the next frame.

[0006]

In the conventional active matrix liquid crystal display device, at the time of driving, the whole screen is displayed in the frame inversion method, in the scanning line direction in the gate line inversion method, and in the drain line inversion method. There is a problem that flicker of the frame frequency f is conspicuous in each signal line direction.

[0007]

An active matrix liquid crystal display device according to the present invention comprises a plurality of scanning electrodes arranged in parallel with each other, a plurality of signal electrodes arranged so as to intersect the scanning electrodes, and a matrix. And a switching element provided for each pixel electrode, the control electrode being connected to the scanning electrode, the first main electrode being connected to the signal wiring, and the second main electrode being connected to the pixel electrode. Wherein the switching element has its control electrode alternately connected to a scan electrode on a different side in the direction in which the scan electrode runs, or has its first electrode in the direction in which the signal electrode runs. Are alternately connected to signal electrodes on different sides, and the polarity of the voltage applied to each pixel electrode is
The polarity of the voltage is reversed alternately in the next frame.
Is shall be made to the rolling.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing one embodiment of the present invention. In the figure, 1 is a pixel electrode, 2 is a TFT, and X ₁ to X ₁ .
X _n is the scan electrodes, Y ₁ to Y _m is a signal electrode.

A feature of this embodiment is that the gates of the TFTs are alternately connected to the scanning electrodes on different sides in a row sandwiched between two scanning electrodes.

When the liquid crystal display device thus constructed is driven by the gate-line inversion method, as shown in FIG. 2, positive and negative voltages that are inverted every dot of the screen are applied. . Here, when the polarity of each dot is changed for each frame, AC driving of the liquid crystal is performed for each dot. Then, by applying the inverted positive / negative voltage for each dot of the screen, flicker of the frame frequency f which appears in the scanning line direction in the conventional gate line inversion method is reduced.

FIG. 3 is a plan view showing another embodiment of the present invention. In the present embodiment, in a column sandwiched between two signal electrodes, the source and drain of the TFT are alternately connected to signal electrodes on different sides.

In the liquid crystal display device configured as described above,
When driven by the drain-line inversion method, positive and negative voltages that are inverted for each dot of the screen are applied to the liquid crystal, as in the previous embodiment.

In the above embodiments, a TFT type active matrix liquid crystal display device has been described. However, the present invention is not limited to this. For example, a monolithic IC using a MOS transistor as a switching element
It can also be applied to a liquid crystal display device of the type.

[0014]

As described above, according to the present invention, in the active matrix liquid crystal display device, every other control electrode of the switching element is connected to the scanning electrode on a different side, or the first main element of the switching element is connected. Since every other electrode is connected to a different signal electrode, according to the present invention, the liquid crystal can be driven by a voltage that is inverted for each dot of the screen, and the liquid crystal can be driven by the frame frequency. Flicker can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a pattern of a voltage applied to each display pixel in the embodiment of FIG.

FIG. 3 is a plan view showing another embodiment of the present invention.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a pattern of a voltage applied to each display pixel in a conventional example.

FIG. 6 is a pattern of a voltage applied to each display pixel in a conventional example.

FIG. 7 shows a pattern of a voltage applied to each display pixel in a conventional example.

[Explanation of symbols]

1 pixel electrode 2 thin film transistor (TFT) X ₁ ~X _n scan electrodes Y ₁ to Y _m signal electrodes

Claims (2)

(57) [Claims] A plurality of scanning electrodes arranged in parallel with each other, a plurality of signal electrodes arranged so as to intersect the scanning electrodes, pixel electrodes arranged in a matrix, and a plurality of scanning electrodes arranged in a matrix. The control electrode is connected to the scan electrode,
A switching element provided along two adjacent scanning electrodes in an active matrix liquid crystal display device comprising: a switching element having a main electrode connected to a signal wiring and a second main electrode connected to a pixel electrode. Has its control electrodes alternately connected to different scanning electrodes, and its first main electrodes connected to different signal electrodes.
And applied to all signal electrodes every time a scanning electrode is selected
The polarity of the applied voltage is reversed, and the same image is
Active matrix liquid crystal display device the polarity of the voltage applied to the pixel electrode is characterized that you inversion. 2. A plurality of scanning electrodes arranged in parallel with each other, a plurality of signal electrodes arranged to intersect with the scanning electrodes, pixel electrodes arranged in a matrix, and a plurality of scanning electrodes provided for each pixel electrode. The control electrode is connected to the scan electrode,
A switching element provided along two adjacent signal electrodes in an active matrix liquid crystal display device comprising: a main electrode connected to a signal line; and a switching element connected to a pixel electrode. Has its first main electrode connected alternately to signal electrodes on different sides, its control electrode connected to different scan electrodes, and the polarity of the voltage applied between adjacent signal electrodes.
Is inverted and applied to each signal electrode in the next frame
Active matrix liquid crystal display device polarity of the voltage is characterized that you inversion.