JPS6313552B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for driving a plasma display panel, and more particularly, to a method for driving a plasma display panel that can use a simplified pilot circuit.

Plasma display panel (PDP) is
As is well known, electrodes covered with a dielectric layer are placed facing each other with a space filled with an ionizable discharge gas such as neon, and an alternating maintenance voltage is constantly applied between the electrodes on both sides. By applying a write pulse voltage selected to exceed the discharge voltage at When a spot is generated and the polarity of the wall voltage is reversed, a discharge spot is continuously generated and a memory display can be performed.

In general, from the time when a voltage higher than the discharge start threshold is applied until the steady space charge distribution of the discharge is formed, there is a discharge spark formation time T _f and a discharge spark formation time T f that first ionizes the discharge gas and causes an avalanche phenomenon. There is a delay characteristic due to a statistical delay time T _s determined by the number of existing electrons that is a factor. In a plasma display panel (PDP), the initial electrons that cause this avalanche phenomenon may include diffusion of charged particles generated by discharge, electron supply due to collisions of metastable atoms, photoexcitation by ultraviolet rays, etc.

Conventionally, in plasma display panels (PDPs), a discharge spot is constantly formed near the display discharge point in order to supply initial electrons to the discharge point and start the discharge easily and reliably. The use of fire discharge points has been practiced. Figure 1 shows a plasma display panel (PDP) with a conventional pilot electrode.
A schematic configuration is shown. FIG. 2 shows voltage waveforms applied to each electrode of the plasma display panel of FIG.

In the PDP shown in FIG. 1, a discharge gas space is formed between first and second dielectric layers 1 and 2, which are provided facing each other. A mutually parallel display electrode set XP provided along the X direction and a pilot electrode set XT provided between the XP electrodes are embedded in the first dielectric layer 1. Further, the second dielectric layer 2 is provided with a display electrode set YP and a pilot electrode set along the Y direction perpendicular to the X direction.
YT is embedded. The outputs of drive circuits DX and DY are connected to the two sets of pilot electrodes XT and YT, respectively.

A discharge sustaining voltage V _XS as shown in Fig. 2 is applied to the display electrode group XP, and the display electrode group
A discharge sustaining voltage _VYS is applied to YP. The peak value V _S of each pulse of the discharge sustaining voltage V _XS and V _YS is
It is selected to be lower than the discharge starting voltage V _f and higher than the minimum discharge sustaining voltage V _SM when a wall voltage is present. When performing display writing to a specific display discharge point, for example, the point indicated by A in Fig. 1, a write pulse as shown in Fig. 2 is applied to the display electrodes X _A and Y _A corresponding to point A. Voltage V _W1 ,
V _W2 is applied, a discharge spot is generated at point A, and a wall voltage is formed. At the display discharge point A written in this way, a discharge of opposite polarity occurs due to the discharge sustaining pulse of the opposite phase applied to the display electrode _YA .
The polarity of the wall voltage is reversed. Below, discharge sustaining voltage
The display state is continued by being alternately discharged by V _XS and V _YS . To erase the display state at point A, press the display electrode X _A or Y _A
It is sufficient to apply an erasing voltage having a peak value or pulse width that produces a discharge spot but is insufficient to form a wall voltage.

As shown in FIG. 2, a pilot ignition voltage V XT that is synchronized with V _XS applied to the display electrode XP is applied to the pilot electrode _XT in the conventional PDP shown in FIG. The other pilot electrode YT has V _YS
A pilot ignition voltage V _YT synchronized with is applied. Therefore, the potential difference at the pilot discharge point between the display electrode XP and the pilot electrode YT is as shown by V _XS-YT in Figure 2, and pilot discharge occurs as shown by SPX. . Further, the potential difference between the display electrode YP and the pilot electrode XT is shown by VYS _-XT , and the pilot discharge is shown by SPY.

In the driving method of the PDP pilot discharge circuit described above, the pilot discharge is performed at the same time as the discharge sustaining voltage is applied, so when the write voltage is applied, the pilot discharge generated by the pilot discharge A write misaddress may occur because metastable atoms and the like are in a decayed state and the pilot effect is about to disappear. In addition, since voltages of different phases are applied to the pilot electrodes in the X direction and Y direction, the drive circuit has two
There is a problem in that it requires multiple sets.

In view of the above-mentioned problems of the conventional type, the main object of the present invention is to simplify the device and reduce the cost by driving the pilot electrode with one drive circuit in a plasma display panel provided with a pilot electrode. The object of the present invention is to reduce the amount of noise and ensure display writing operations.

The present invention uses an AC drive system and has two sets of pilot flame electrodes perpendicular to each other.
In the display panel, the two sets of pilot flame electrodes are driven by a single pilot flame drive circuit, and
The plasma display is characterized in that the discharge sustaining voltage is applied to the direction and Y direction display electrodes at zero volts during the application period, and during the other periods, a pilot flame drive voltage waveform that is the pilot flame voltage (V _T ) is applied.
A driving method for the panel is provided.

A driving method for a plasma display panel as an embodiment of the present invention will be explained below with reference to FIGS. 3 and 4. FIG. Figure 3 shows the above
4 is a schematic configuration diagram of an apparatus using a PDP driving method, and FIG. 4 is a voltage waveform diagram for explaining the operation of the apparatus.

In the device shown in FIG. 3, unlike the case shown in FIG. 1, two sets of pilot flame electrodes XT and YT are connected to the output of one pilot flame drive circuit TD. The configuration of the PDP is the same as that shown in FIG. The display electrodes XP and YP include
Discharge sustaining voltages V _XS and V _YS as shown in Fig. 4
(similar to that of FIG. 2) are respectively applied.
Pilot ignition voltages shown as V _XT and V _YT in FIG. 4 are applied to the pilot electrodes XT and YT. These pilot flame ignition voltages V _XT and V _YT are supplied to the electrodes XT and YT by a single pilot flame drive circuit TD. The pilot voltage V _T is applied to the electrodes XT and YT at a timing when the discharge sustaining voltages V _XS and V _YS are not applied.

The potential difference at the discharge point between the display electrode XP and the pilot electrode YT is expressed as V _XS-YT in FIG. 4, and the pilot discharge at this discharge point is indicated as SPX. In addition, display electrode YP and pilot electrode
The potential difference at the discharge point between XT is shown in Figure 4.
It is expressed as V _YS-XT , and the pilot discharge at this discharge point is indicated as SPY. As shown in the discharge waveforms SPX and SPY, the pilot discharge is performed not only when the discharge sustaining voltage is applied, but also when the discharge sustaining voltage falls. Therefore, it has a pilot effect for display discharge in the display section, and
The pilot effect on the write pulse is also improved over the prior art described above.

The pilot ignition circuit TD includes an inverter IV, a capacitor C, resistors R1, R2, a transistor TR1,
It is composed of TR2 and diode D, and outputs a high voltage waveform corresponding to the pulse waveform input to the input terminal IN.

According to the present invention, a plasma generator equipped with a pilot electrode is provided.
In the display panel, two sets of pilot electrodes can be driven by one drive circuit,
Timing control becomes easy, the device can be simplified and the cost can be reduced, and the display writing operation can be ensured.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a schematic configuration of a plasma display panel using a conventional drive method, and Fig. 2 is a voltage waveform diagram for explaining the PDP drive method of Fig. 1. FIG. 3 is a diagram showing a schematic configuration of a device using a PDP driving method as an embodiment of the present invention, and FIG.
FIG. 3 is a voltage waveform diagram for explaining the driving method of FIG.

Claims (1)

[Scope of Claims] 1. In a drive circuit for a plasma display panel that is an AC drive system and has two sets of pilot flame electrodes that are perpendicular to each other, the two sets of pilot flame electrodes are driven by a single pilot flame. Driven by a circuit, the discharge sustaining voltage application period to the X-direction and Y-direction display electrodes is zero volts,
During other periods, a plasma driving voltage waveform serving as the pilot flame voltage (V _T ) is applied.
Display panel drive method.