KR20050113857A - Plasma display device and driving method thereof - Google Patents

Abstract

The present invention provides a plasma display device and a driving method thereof, wherein a scan electrode is divided into an odd group and an even group, and when a sustain waveform is applied to the odd group and even group scan electrodes, the scan electrodes and the sustain electrodes are applied with a time difference. Disperses maintenance discharges in the liver. According to the present invention, it is possible to reduce the influence of the impedance of the driving board by dispersing the sustain light, and to prevent the discharge instability due to the distortion of the sustain waveform.

Description

Plasma display device and driving method thereof {PLASMA DISPLAY DEVICE AND DRIVING METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device, and more particularly, to a method of driving a plasma display panel in a sustain period.

Plasma display devices are flat display devices that display characters or images using plasma generated by gas discharge, and dozens to millions or more of pixels are arranged in a matrix form according to their size. First, a structure of a general plasma display panel will be described with reference to FIGS. 1 and 2.

1 is a partial perspective view of a plasma display panel, and FIG. 2 shows an electrode arrangement diagram of the plasma display panel.

As shown in Fig. 1, the plasma display panel includes two glass substrates 1 and 6 facing each other apart. On the glass substrate 1, the scan electrode 4 and the sustain electrode 5 are formed in pairs and in parallel, and the scan electrode 4 and the sustain electrode 5 are covered with the dielectric layer 2 and the protective film 3. have. A plurality of address electrodes 8 are formed on the glass substrate 6, and the address electrodes 8 are covered with the insulator layer 7. The address electrode 8 and the partition 9 are formed on the insulator layer 7 between the address electrodes 8. In addition, the phosphor 10 is formed on the surface of the insulator layer 7 and on both sides of the partition wall 9. The glass substrates 1 and 6 are disposed to face each other with the discharge space 11 therebetween so that the scan electrode 4, the address electrode 8, the sustain electrode 5, and the address electrode 8 are orthogonal to each other. The discharge space 11 at the intersection of the address electrode 8 and the paired scan electrode 4 and the sustain electrode 5 forms a discharge cell 12.

Here, the wall charge refers to a charge that is formed on the wall of the discharge cell (eg, the dielectric layer) close to each electrode and accumulates in the electrode. This wall charge is not actually in contact with the electrode itself, but here the wall charge is described as "formed", "accumulated" or "stacked" on the electrode. In addition, a wall voltage refers to the potential difference formed in the wall of a discharge cell by wall charge.

In addition to forming a discharge space, the partition wall blocks light generated during discharge to prevent cross talk of neighboring pixels. A plurality of such unit structures are formed on a single substrate in a matrix form, and a fluorescent material is applied to each unit structure to form one pixel, and the pixels are gathered to form a plasma display panel. Plasma display panels, which are currently commercialized, generate a discharge in each pixel, and excite a fluorescent material coated on the inner wall of the pixel with ultraviolet rays generated by the discharge to realize a desired color.

As shown in FIG. 2, the electrode of the plasma display panel has a matrix structure of n × m. In the column direction, address electrodes A ₁ -A _m are arranged, and in the row direction, n rows of scan electrodes Y ₁ -Y _n and sustain electrodes X ₁ -X _n are arranged in pairs.

In order to achieve the performance as a color display, the plasma display device needs to implement a halftone. Currently, a halftone implementation method of dividing one TV field into a plurality of subfields and controlling the time division is used. have.

3 is a half gray scale implementation method of an AC plasma display panel that is generally applied.

FIG. 3 is a 6-bit gray scale implementation method, and one TV field is divided into six subfields. In FIG. 3, 6 is represented, but 6 to 12 or various numbers are provided.

Each subfield consists of a reset period, an address period, and a sustain period. The reset period serves to erase the wall charges formed by the previous sustain discharge and to set up the wall charges in order to stably perform the next address discharge. The address period is a period in which a wall charge is accumulated in a cell (addressed cell) that is turned on by selecting a cell that is turned on and a cell that is not turned on in the panel. The sustain period is a period in which sustain discharge is performed to actually display an image in the addressed cells.

4 is a view showing a driving waveform of a conventional plasma display device.

In Fig. 4, the driving waveform of the sustain section is shown. In the conventional sustain discharge, all the cells are discharged at the same time by alternately applying pulse waves to the X and Y electrodes.

In this conventional driving method, since all the cells discharge simultaneously, the magnitude of the discharge current is large, thereby increasing the current drop due to the impedance of the driving board. This phenomenon occurs severely in a large inch plasma display device having a large discharge current, and has a problem of causing discharge instability due to distortion of the sustain waveform.

The technical problem to be achieved by the present invention is to solve the problems of the prior art described above, plasma is applied to the entire scan electrode line to even and odd line group by dispersing the discharge current by applying a sustain waveform to each group with a time difference It is to provide a display device and a driving method thereof.

The plasma display panel according to one aspect of the present invention for solving the above problems,

A plasma display device which receives image data input from an external source and displays data therein,

A first substrate including a plurality of first and second electrodes that are formed in parallel with each other,

A second substrate having a plurality of third electrodes formed in a direction crossing the first and second electrodes,

A driving circuit for supplying a plurality of sustain waveforms to the plurality of first electrodes of odd and even groups for discharging the discharge cells formed by the adjacent first, second and third electrodes,

The drive circuit,

The sustain waveform is applied to the odd group and the even group at a time difference.

The driving method of the plasma display panel according to another aspect of the present invention for solving the technical problem,

A plurality of first electrodes and a second electrode formed on a first substrate, and a plurality of third electrodes intersecting the first and second electrodes and formed on a second substrate, respectively; A method of driving a plasma display device by dividing a into an odd group and an even group and applying a plurality of sustain waveforms to the first group of odd and even groups.

The sustain waveform is applied to the odd group and the even group at a time difference.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

5 is a configuration diagram of a plasma display device according to an exemplary embodiment of the present invention.

Referring to FIG. 5, a plasma display device according to an exemplary embodiment of the present invention includes a plasma display panel 100, a controller 200, an address electrode driver 300, and a scan electrode driver (hereinafter referred to as a “Y electrode driver”). 400 and a sustain electrode driver (hereinafter referred to as an 'X electrode driver') 500.

The plasma display panel 100 includes a plurality of address electrodes A1-Am arranged in a column direction, a plurality of sustain electrodes (hereinafter referred to as 'X electrodes') (X1-Xn) and scans arranged in a row direction. Electrodes (hereinafter referred to as 'Y electrodes') Y1-Yn. The X electrodes X1-Xn are formed corresponding to the respective Y electrodes Y1-Yn, and generally have one end connected in common to each other. The plasma display panel 100 includes a glass substrate (not shown) in which the X and Y electrodes X1-Xn and Y1-Yn are arranged, and a glass substrate (not shown) in which the address electrodes A1-Am are arranged. Is done. The two glass substrates are disposed to face each other with the discharge space therebetween so that the Y electrodes Y1-Yn and the address electrodes A1-Am and the X electrodes X1-Xn and the address electrodes A1-Am are orthogonal to each other. At this time, the discharge space at the intersection of the address electrodes A1-Am and the X and Y electrodes X1-Xn and Y1-Yn forms a discharge cell. The controller 200 receives an image signal from the outside and outputs an address driving signal, an X electrode driving signal, and a Y electrode driving signal. The controller 200 divides and drives one frame into a plurality of subfields, and each subfield includes a reset period, an addressing period, and a sustain period. In particular, the controller 200 drives the entire scan electrode by dividing the even and odd groups, and applies a sustain waveform with a time difference between the even and odd groups in the sustain period of at least one subfield.

The address electrode driver 300 receives an address electrode driving signal from the controller 200 and applies a display data signal for selecting a discharge cell to be displayed to each address electrode A1-Am. The X electrode driver 500 receives an X electrode driving signal from the controller 200 and applies a driving voltage to the X electrodes X1 to Xn. The Y electrode driver 400 receives the Y electrode driving signal from the controller 200 and applies a driving voltage to the Y electrodes Y1-Yn.

The operation of the plasma display device according to the embodiment of the present invention having such a configuration will now be described in detail.

First, the controller 200 receives an externally input image signal, corrects a gamma value according to the characteristics of the plasma display panel, generates the corrected image signal into N subfields, and generates an address electrode driving signal for each subfield. Output

The controller 200 calculates the load ratio of the gamma corrected image signal and generates and outputs an X electrode driving signal and a Y electrode driving signal with a sustain number corresponding to the current load ratio.

In addition, the X electrode driver 500 generates the waveform shown in FIG. 6 at the X electrode in the sustain period in response to the X electrode driving signal received from the controller 200.

In addition, the Y electrode driver 400 generates the waveform shown in FIG. 6 in the sustain period in response to the Y electrode driving signal received from the controller 200. That is, the Y electrode driver 400 applies a sustain waveform in the sustain period by dividing the entire scan electrode or the scan electrode line into an even group and an odd group. In this case, the sustain waveform applied to the even group is a phase shifted waveform of the sustain waveform applied to the odd group.

According to the exemplary embodiment of the present invention, the Y electrode is divided into an even group and an odd group, and a sustain waveform having a phase shift is applied to each electrode group to spread the discharge current. In addition, since the discharge generated during falling (falling) is stronger than the discharge generated during the rising (rising) of the sustain waveform, the discharge occurs evenly to the even and odd groups for one period.

This discharge process will be described in detail with reference to FIG. 7 as follows.

7 is a view showing the state of the wall charge of each line according to the driving waveform according to an embodiment of the present invention.

Referring to FIG. 7, a sustain waveform is periodically applied to the X electrode, which is a common electrode, and a sustain waveform is applied to the even and odd groups of Y electrodes, while an odd group of Y electrodes is applied to the even electrodes. In contrast, a sustain waveform with a phase shift of about 1/2 of the sustain waveform width is applied. In other words, the waveforms applied to the odd and even groups have the same shape and only phase shift.

Here, at time point 1, when the sustain waveform is applied to the X electrodes, the charges of the X electrodes and the odd-numbered Y electrodes move in opposite directions, and discharge occurs between the odd-numbered Y electrodes and the X electrodes.

Next, at time 2, since the sustain waveform applied to the even-numbered Y electrodes rises, charges of the X electrode and the even-numbered Y electrodes move in opposite directions, and a discharge occurs between the even-numbered Y electrodes and the X electrodes.

Next, at the time point 3, since the sustain waveform applied to the X electrode rises, charges of the X electrode and the odd-numbered Y electrode move in opposite directions, and discharge occurs between the odd-numbered Y electrode and the X electrode.

Then, at the time point 4, since the sustain waveforms applied to the even-numbered Y electrodes are polled, the charges of the X-electrode and the even-numbered Y electrodes move in opposite directions, and a discharge occurs between the even-numbered Y electrodes and the X electrodes.

In the subfield to which a plurality of sustain waveforms are applied, the processes of the time points 1, 2, 3, and 4 are repeated many times, and the process may not be performed in the lowest subfield.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the exemplary embodiment of the present invention, the sustain light is dispersed in the plasma display panel, thereby reducing the influence of the impedance of the driving board and preventing the discharge instability due to the distortion of the sustain waveform.

1 is a schematic partial perspective view of a typical plasma display panel.

2 is an electrode array diagram of a general plasma display panel.

3 is a diagram illustrating a method of implementing gray scales of an AC plasma display device, which is generally applied.

4 is a view showing a driving waveform of a conventional plasma display device.

5 is a configuration diagram of a plasma display device according to an exemplary embodiment of the present invention.

6 is a driving waveform diagram of a plasma display device according to an exemplary embodiment of the present invention.

7 is a view showing the state of the wall charge of each line according to the driving waveform according to an embodiment of the present invention.

Claims (10)

A plasma display device which receives image data input from an external source and displays data therein, A first substrate including a plurality of first and second electrodes that are formed in parallel with each other, A second substrate having a plurality of third electrodes formed in a direction crossing the first and second electrodes, And a driving circuit for supplying at least one sustain waveform to the plurality of first electrodes formed of an odd group and an even group. The drive circuit, And applying the sustain waveform to the first electrode of the odd-numbered group and the first electrode of the even-numbered group with a time difference. The method of claim 1, The difference between the time point of the discharge occurring between the even group and the second electrode and the time point of the discharge occurring between the odd group and the first electrode and the second electrode corresponds to the time difference. Display. The method of claim 1, And the sustain waveforms applied to the even-numbered first electrodes have the same shape as the sustain waveforms applied to the odd-numbered electrodes and are out of phase. The method of claim 1, And a sustain waveform applied to the first group of odd-numbered groups and a sustain waveform applied to the second electrode of the same shape. The method of claim 4, wherein The sustain waveforms applied to the odd-numbered first electrodes and the sustain waveforms applied to the second electrodes are alternately applied, and the time point at which the sustain waveforms are applied to the odd-numbered first electrodes and the sustain waveforms to the second electrodes are alternately applied. And a sustain waveform is applied to the even-numbered first electrodes in the middle of the time point at which it is applied. The method of claim 1, And the second electrode is a common electrode. A plurality of first electrodes and a second electrode formed on a first substrate, and a plurality of third electrodes intersecting the first and second electrodes and formed on a second substrate, respectively; A method of driving a plasma display device by dividing a into an odd group and an even group and applying a plurality of sustain waveforms to the first group of odd and even groups. And applying the sustain waveform to the first electrode of the odd group and the first electrode of the even group with a time difference. The method of claim 7, wherein And the first electrode is a scan electrode, and the second electrode is a sustain electrode. The method of claim 7, wherein The difference between the time point of the discharge occurring between the even group and the second electrode and the time point of the discharge occurring between the odd group and the first electrode and the second electrode corresponds to the time difference. Method of driving display device. The method of claim 7, wherein The sustain waveforms applied to the odd-numbered first electrodes and the sustain waveforms applied to the second electrodes are alternately applied, and the time point at which the sustain waveforms are applied to the odd-numbered first electrodes and the sustain waveforms to the second electrodes are alternately applied. And a sustain waveform is applied to the even-numbered first electrodes in the middle of the time point at which it is applied.