JPS6327892A - Driving of plasma display device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for driving a plasma display, and particularly to a method for driving a plasma display (AC refresh type plasma display).
).

Conventionally, as a driving method for this type of AC refresh type plasma display (FDP), a voltage waveform applied to either one of an insulator and an external electrode group facing each other with a discharge space is time-divisionally applied. When the voltage waveform applied to the one electrode group is turned on, a pulse voltage with the opposite phase is applied to the other electrode group, and when the voltage waveform is not turned on, a voltage with the same phase is applied to the other electrode group. It is shown in Japanese Patent Publication No. 55-48318 that stable operation can be achieved by applying .

In the conventional driving method described above, pulse voltages of opposite phase and the same phase are applied to each electrode of the electrode group formed on the same insulator in response to lighting and non-lighting. Electrically, the drive circuit is coupled through the stray capacitance between the respective electrodes, and when a lighting or non-lighting state occurs between adjacent electrodes, the power consumption of the drive circuit becomes maximum. Furthermore, the brightness of 1ACIJ Fresh FDP is determined by the number of pulses included in a unit time, but as the number of pulses increases, the power consumption of the drive circuit increases, so the drive frequency is limited and it is difficult to obtain sufficient brightness. The disadvantage was that it was difficult to

On the other hand, if a time lag occurs between the high-frequency pulses applied to the scanning electrode group and the data electrode group,
The operation differs from that disclosed in No. 8318, and the driving voltage range is narrow.

Furthermore, when a transparent electrode is used as the data side electrode, a distributed constant circuit is formed by the stray capacitance between this transparent electrode and the electrode, and the output of the drive circuit and the waveform at the tip of the transparent electrode are , and because the voltages are different, there is a drawback that uneven brightness occurs.

The present invention provides a driving method that eliminates the drawbacks of the above-described conventional phase select driving method for an ACIJ fresh type plasma display.

That is, depending on the presence or absence of display, the waveform of the voltage applied to the row electrodes and the period during which a waveform voltage with the opposite phase or the same phase as the voltage applied to the row electrodes is applied to the column electrodes and the waveform of the voltage applied to the row electrodes, as in the conventional phase selection method. The scanning period includes a period in which a voltage completely unrelated to the voltage is applied to the column electrodes, and the power consumed during the period in which a voltage similar to that in the conventional 7A selection method is applied is Although it is the same as the phase selection method, the power consumed during the period when a voltage completely unrelated to the waveform of the voltage applied to the row electrodes, that is, a DC voltage is applied to the column electrodes, is dissipated between the column electrodes. The amount of power consumed becomes negligible, so it is significantly reduced.

The driving method of the ACI77 reciprocating plasma display of the present invention is that an electrode group is formed on a glass plate, and the electrode group connects two glass plates covered with a dielectric material, with the dielectric material facing each other and maintaining an appropriate distance. When driving a plasma display panel by applying a pulsed voltage between the electrodes, the plasma display panel has a structure in which the periphery is hermetically sealed with a glass lift and neon gas is filled inside. When a pulse voltage is applied to the electrode and the other electrode is kept at O potential to cause a discharge between the electrodes, one discharge cell in the plasma display panel sets the discharge voltage to the minimum single-blade discharge starting voltage (VDmin). , if the voltage at which all cells of the plasma display panel discharge is defined as the maximum discharge starting voltage (VDmax), one electrode of the plasma display has a voltage higher than VDmin (, VDm
Apply a low pulsed voltage (vO) to ax and υ,
The other electrode is supplied with a pulsed voltage (vl
), when the condition of VDmin)IVOI-IVII is satisfied, the discharge stops and VDmax(lvQl+
This is an improved driving method that utilizes the fact that discharge starts when the condition of 1M1L is satisfied.

When a pulsed voltage higher than the maximum single-blade discharge starting voltage is applied to one electrode and a DC voltage is applied to the other electrode, all cells in the panel start discharging, but only after the voltage is applied. It takes time for discharge to start, and although it varies depending on the applied voltage, the discharge delay time in the AC refresh method is generally 5 microseconds or more. On the other hand, the discharge response after discharge is started is very fast, taking less than 100 nanoseconds.

The driving method of the ACIJ fresh type plasma display of the present invention utilizes this discharge delay phenomenon, and applies a pulsed voltage higher than the single-blade discharge starting voltage to one electrode, and displays the same as the conventional phase selection method. A pulsed voltage of the same phase or opposite phase is applied to the other electrode according to the presence or absence of the voltage, and the discharge cells that should be discharged are discharged, and the discharge cells that are not to be discharged are not discharged. The voltage is removed and the state is maintained with a pulsed voltage applied to only one electrode, and before the non-lit cells are lit with the pulsed voltage of one electrode, the conventional 7
This is a method of driving the FDP by repeating the process of returning to the same state as the aids selection method.

That is, if the state driven by the conventional 7-Aze selection method is defined as the address state, and the state in which the address state is maintained by applying a pulsed voltage to one electrode is defined as the hold state, then the drive method of the present invention is defined as It is characterized by repeating the address state and hold state alternately.

Next, a detailed description will be given with reference to the drawings.

FIG. 1 is a timing chart of voltage arrangement according to the first embodiment of the present invention. FIG. 2 is a timing chart for explaining the timing of pulsed voltages applied to the scanning electrodes.

The plasma display panel used in the driving method of the present invention consists of two glass plates each having electrode groups covered with a dielectric, the electrode groups facing each other, each electrode group intersecting at right angles, and the intersection point being the light emitting point for display. It is designed to be. To drive this plasma display panel, generally the horizontal synchronizing signal υH shown in 2-E in FIG.
During the period, the first electrode is selected, and a pulsed voltage having a peak value VQ shown at 2-A in FIG. 2 is applied to the first electrode. In the case of a panel having m horizontal electrodes and n vertical electrodes, n vertical electrodes are selected and driven relative to the first horizontal electrode.

Next, after a certain period (blanking period), the second
The electrode is selected, □Similar to the first electrode, v
A pulsed voltage having a peak value of O is applied to the second electrode. (Refer to Fig. 2-2-B) A pulsed voltage is applied to the third electrode after the pulsed voltage is applied to the second electrode, and this operation is repeated sequentially, and the vertical synchronizing signal is It lasts for a period (V) until it enters. The state in which the first electrode can be selected is returned by the vertical synchronizing signal shown in FIG. 2 2-D.

That is, in the scanning method of the present invention, scanning is performed sequentially using a horizontal synchronizing signal, and after all horizontal electrodes have been scanned, the original state is restored using a vertical synchronizing signal that is input. The vertical synchronization signal matches the display refresh frequency and is generally selected to be 60 cycles or more. On the other hand, although the number of horizontal synchronization signals included in one period of the vertical synchronization signal matches the number of scan lines, generally the number of scan lines does not match the number of scan electrodes of the panel.
The number of scanning lines is greater than the number of scanning electrodes on the panel.

1-A in FIG. 1 shows a pulsed voltage applied to the first row electrode, and 1-B and 1-C in FIG. 1 indicate the m-th column and n-th column, respectively.
It shows the pulsed voltage applied to the column electrodes.

1-C and 1-D in FIG. 1 are the first row electrode and the mth row electrode, respectively.
A discharge light emitting point (
The voltage waveforms applied to the cell (row 1, column m) and the cell (row 1, column n) are shown.

Since the voltage waveform applied to the m-th column electrode is in opposite phase to the voltage waveform applied to the first row electrode, (1st row, m
column) cell is in lighting mode.

On the other hand, since the pulsed voltage applied to the n-th column electrode is in phase with the pulsed voltage applied to the first row electrode (1st row, nth column), the cell is in a non-lighting mode, that is, a light-off mode. It is. (1st row, m column) The pulsed voltage applied to the cell is expressed by the potential difference between the pulsed voltage applied to the 1st row electrode and the mth column electrode, and has the waveform 1-D in Figure 1. . (
Similarly, the pulsed voltage applied to the cell (row 1, column n) is expressed as a potential difference as shown in FIG. 1-E.

In the driving method according to the present invention, during the H period when the row electrodes are fully selected, there is a period a in which a pulsed voltage is applied to the column electrodes depending on whether or not there is a display, and a period b in which a DC voltage is applied regardless of the display. This method differs from conventional phase selection methods in that it determines the following.

The operation in period a during period H is exactly the same as in Japanese Patent Publication No. 55-48318), and this period is defined as an address state in the present invention. On the other hand, as shown in FIG. 1-D and 1-E, the voltages applied to the lit cells and unlit cells during the b period of the H period are exactly the same regardless of whether the lights are on or off. Defined as a hold state. First, the operation in the address state is VDmax(lV11+1VOI−(1)
VDmin) l vo l-l vl l +
2) + If the conditions of 1) and 12) are met, cells that should be lit will be lit, and cells that should not be lit will be turned off. O Hold mode is the period (a) in Figure 1 1-D and 1-H. As shown in the voltage waveform of , a pulse voltage with an amplitude of (VO) is applied regardless of whether the light is on or off, and the state created in the address state, which is applied prior to the hold state, is maintained during this period. It is intended to be maintained and displayed.

In other words, the cell in row 01, column m, which is lit in the address state, discharges during period (a) and is filled with charged particles generated by the discharge, so the voltage is lower than in the address state. Discharge starts easily even in the hold state where is applied.

On the other hand, in the cell (1st row, n column) that is not lit in the address state, the applied voltage is lower than the discharge start voltage during the address state period, and there are no charged particles in the cell (1st row, n column), and the discharge does not occur. a
A certain amount of time is required to start discharging at the voltage applied during the subsequent period b without starting during the period b,
By appropriately selecting period b, it is possible to determine a voltage at which discharge does not start in the hold state.

The above driving method will be described with reference to an example in which a plasma display having 640×400 dots is driven.

The applied voltage Vo in Fig. 1-A is 180V, and its frequency is 8.
00 KHz, applied voltage v1 of Figure 1 1-B, 1-C
30v1 its frequency 800KHz %a period 20
When the b period was set to 10 microseconds, stable operation was obtained and the following results were obtained.

Conventional phase selection method Invention power 40W 28W brightness
IQfL 9.4fL

[Brief explanation of the drawing]

FIG. 1 shows applied voltage waveforms in an embodiment of the present invention. FIG. 1 1-A shows the pulse voltage applied to the scanning electrode of the first row, and FIG. 1 1-B shows the m-th column data side electrode,
-1- Fig. 1-C shows the pulse shapes applied to the n-th column data electrodes. 1-D and 1-E in FIG. 1 respectively show the state of the voltage applied to the cells (row 1, column m) and (row 1, column n). FIG. 2 shows the state of the pulsed voltage applied to the scanning electrodes. Strategy l Diagram

Claims (1)

[Claims] A voltage is sequentially applied in a time-division manner to one scanning electrode group of a plasma display panel whose electrodes are covered with a dielectric material to perform scanning, and the voltage applied to each scanning electrode is In a plasma display refresh drive method in which a voltage is applied to other data-side electrode groups in synchronization with each other depending on the presence or absence of data, there is a period and a hold period in which display is performed in an address state during at least one scanning period. 1. A method of driving a plasma display, comprising: a period of displaying in a certain state. Note that the address state and hold state referred to here are defined as follows. That is, in synchronization with the pulsed voltage applied to the scan electrode during one scan period when one scan electrode is selected, and in addition, the data side electrode corresponding to the cell to be displayed has an opposite phase, and the cell that should not be displayed is synchronized with the pulse voltage applied to the scan electrode. The state during which a pulsed voltage of the same phase is applied to the data-side electrode corresponding to the display is called the address state, and the pulsed voltage that had been applied to the data-side electrode is stopped, and the charge created in the address state is called the address state. A state during a period in which the particles are driven only by pulsed voltages applied to the scanning electrodes is defined as a hold state.