JP2002149110A - Method for driving plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that when a wall voltage accumulated on each electrode for the last write period and sustaining period is weakened in the initialization operation in an initialization period including the sustaining period in a conventional driving method, the wall voltage cannot be recovered before the write operation in the following write period is normally performed so that the write operation cannot normally be carried out. SOLUTION: In the initialization period in the initialization period including the sustaining period in driving a plasma display, a voltage Vr (V) exceeding the break-down voltage against column electrode is applied to the 1st row electrode after the sustaining operation in the sustaining period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a driving method of a plasma display for displaying an image by controlling discharge.

[0002]

2. Description of the Related Art FIG. 8 is a partial perspective view of a plasma display panel (hereinafter referred to as a panel). As shown in FIG. 8, a dielectric layer 2 and a protective film 3 are formed on a first glass substrate 1.
The scanning electrode 4 and the sustaining electrode 5 covered with are paired and provided in parallel with each other. Data electrodes 8 covered with an insulator layer 7 are provided on the second glass substrate 6, and partitions 9 are provided on the insulator layer 7 between the data electrodes 8 in parallel with the data electrodes 8. . Further, a phosphor 10 is provided from the surface of the insulator layer 7 to the side surface of the partition wall 9, and the scanning electrode 4 is provided.
And the first such that the sustain electrode 5 and the data electrode 8 are orthogonal to each other.
Of the glass substrate 1 and the second glass substrate 6
Are arranged facing each other. The scanning electrode 4 sandwiched between two adjacent partitions 9 and facing the data electrode 8
A discharge cell 12 is formed in the discharge space at the intersection of the electrode and the sustain electrode 5.

Next, FIG. 9 shows an electrode arrangement diagram of this panel. As shown in FIG. 9, the electrode array of this panel 100 has an M × N matrix configuration, and M columns of data electrodes D1 to DM are arranged in the column direction, and N rows of scanning electrodes are arranged in the row direction. SCN1 to SCNN and sustain electrode SUS1
SUSN are arranged.

FIG. 10 is a diagram showing a timetable structure in a conventional driving method for driving this panel, and FIG. 11 is an operation timing diagram thereof. In this driving method, one field is composed of a plurality of subfields, for example, eight subfields. Each of these subfields is composed of an initialization period including a writing period and a sustain period. Erasing period, followed by a plurality of subfields and an erasing period at the end of the field.

The initialization period at the beginning of one field will be described below with reference to FIG. As shown in FIG. 11, in the initialization operation in the initialization period, all the data electrodes D1 to DM and all the sustain electrodes SUS1 to SUSN are set to 0.
(V), and all the scan electrodes SCN1 to SCNN move from a voltage Va (V) lower than the discharge start voltage to a voltage Vb (V) higher than the discharge start voltage for all the sustain electrodes SUS1 to SUSN. A ramp voltage that rises slowly. While this ramp voltage rises, in all the discharge cells 12, all the scan electrodes SCN1 to SCNN
From all data electrodes D1 to DM and all sustain electrodes S
The first weak discharge occurs in each of US1 to SUSN, a negative wall voltage is accumulated on the surface of protective film 3 on all scan electrodes SCN1 to SCNN, and insulators on all data electrodes D1 to DM A positive wall voltage is accumulated on the surface of the layer 7 and the surface of the protective film 3 on all the sustain electrodes SUS1 to SUSN.

Thereafter, all the sustain electrodes SUS1 to SUSN
Is maintained at a positive voltage Vh (V), and all the scan electrodes SCN
1 to SCNN are applied to all the sustain electrodes SUS1 to SUSN with a ramp voltage that gradually decreases from a voltage Vc (V) lower than the discharge start voltage to a voltage Vd (V) higher than the discharge start voltage. While this lamp voltage falls, all the sustain electrodes S
All scan electrodes SCN1 to SCN from US1 to SUSN
N, a second weak discharge occurs in each of the N, the negative wall voltage accumulated on the surface of the protective film 3 on all the scan electrodes SCN1 to SCNN, and all the sustain electrodes SUS1 to SUS.
The positive wall voltage accumulated on the surface of the protective film 3 on N is weakened. A weak discharge also occurs between all the data electrodes D1 to DM and all the scan electrodes SCN1 to SCNN, and the positive wall accumulated on the surface of the insulator layer 7 on all the data electrodes D1 to DM. The voltage is adjusted to a value that effectively affects a write operation in a subsequent write period. Thus, the initialization operation in the initialization period at the beginning of one field is completed.

Next, in the write operation in the write period, all the scan electrodes SCN1 to SCNN are held at Vg (V), and all the scan electrodes SCN1 to SCNN correspond to the discharge cells 12 to be displayed on the first row among the data electrodes D1 to DM. Predetermined data electrode D
A positive write pulse voltage Vw (V) is applied to i (i represents an integer of 1 to m), and a scan pulse voltage 0 (V) is applied to the scan electrode SCN1 in the first row. At this time, the voltage between the surface of the insulator layer 7 and the surface of the protective film 3 on the scan electrode SCN1 at the intersection of the predetermined data electrode Di and the scan electrode SCN1 is equal to the write pulse voltage Vw (V). Since the positive wall voltage accumulated on the surface of the insulator layer 7 on the data electrodes D1 to DM is added, at the intersection, a predetermined electrode is provided between the predetermined data electrode Di and the scan electrode SCN1 and the sustain electrode SUS1. And a scanning discharge occurs between the scanning electrode SCN1 and the scanning electrode S at the intersection.
A positive wall voltage is applied to the surface of the protective film
A negative wall voltage is accumulated on the surface of the protective film 3 on the US 1 and a negative wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode Di.

Next, of all the data electrodes D1 to DM, a positive write pulse is applied to a predetermined data electrode Di (i represents an integer of 1 to m) corresponding to the discharge cell 12 to be displayed in the second row. The voltage Vw (V) is changed to the scan electrode SCN2 in the second row.
Is applied with a scanning pulse voltage of 0 (V). At this time, the voltage between the surface of the insulator layer 7 and the surface of the protective film 3 on the scan electrode SCN2 at the intersection of the predetermined data electrode Di and the scan electrode SCN2 is the write pulse voltage Vw.
Since the positive wall voltage accumulated on the surface of the insulator layer 7 on all the data electrodes D1 to DM is added to (V), a predetermined data electrode Di and a scan electrode SCN2 are formed at this intersection. And sustain electrode SUS2 and scan electrode SC
N2, a write discharge occurs, and a positive wall voltage is applied to the surface of the protective film 3 on the scan electrode SCN2 at the intersection and a negative wall voltage is applied to the surface of the protective film 3 on the sustain electrode SUS2. A negative wall voltage is accumulated on the surface of the insulator layer 7 on the electrode Di.

A similar operation is continuously performed, and finally, of all the data electrodes D1 to DM, a predetermined data electrode Di (i is 1) corresponding to the discharge cell 12 to be displayed on the Nth row.
To an integer m), a positive write pulse voltage Vw
(V) is applied a scan pulse voltage 0 to the scan electrode SCNN of the Nth row.
(V) is applied. At this time, the insulator layer 7 at the intersection of the predetermined data electrode Di and the scan electrode SCNN is used.
Between the surface of the protective layer 3 on the scan electrode SCNN and the surface of the insulating layer 7 on all the data electrodes D1 to DM in the write pulse voltage Vw (V). Since the voltages are added, a write discharge occurs between the predetermined data electrode Di and the scan electrode SCNN and between the sustain electrode SUSN and the scan electrode SCNN at the intersection, and the scan electrode at the intersection is formed. SCNN
A positive wall voltage is applied to the surface of the upper protective film 3 by the sustain electrode SUSN.
A negative wall voltage is accumulated on the surface of the upper protective film 3 and a negative wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode Di. Thus, the writing operation in the writing period ends.

FIG. 12 shows an operation timing chart of the initialization period including the sustain period after the writing period in the conventional driving. FIG. 12 shows the maintenance operation and the initialization operation of the initialization period including the maintenance period in this conventional driving method.
This will be described with reference to FIG.

As shown in FIG. 12, the sustain period of each subfield overlaps with the initializing period of the subsequent subfield. During this overlap period, all the scan electrodes SCN1 to SCNN and all the sustain electrodes SUS1 are set. ~
Sustain pulse voltage Vm (V) is alternately applied to SUSN. Then, the pulse width of the last sustain pulse in the sustain period is made shorter than the pulse widths of the other sustain pulses, and thereafter, the scan electrodes SCN1 to SCNN and the sustain electrode SUS1
SUSN to a constant voltage Vh (V).

The sustain operation in the above sustain period will be described below. In the sustain period following the writing operation, first, all the scan electrodes SCN1 to SCNN and the sustain electrodes SUS1 to SUSN are held at 0 (V), and then the positive sustain pulse voltage Vm is applied to all the scan electrodes SCN1 to SCNN.
When (V) is applied, the voltage between the surface of the protective film 3 on the scan electrode 4 and the surface of the protective film 3 on the sustain electrode 5 in the discharge cell 12 in which the write discharge has occurred becomes the sustain pulse voltage Vm (V ), The positive wall voltage of the protective film 3 on the scan electrode 4 accumulated in the writing period and the negative wall voltage accumulated on the surface of the protective film 3 on the sustain electrode 5 are added. Exceeds the firing voltage. Therefore, a sustain discharge occurs between scan electrode 4 and sustain electrode 5 in discharge cell 12 in which the write discharge has occurred, and protective film 3 on scan electrode 4 in discharge cell 12 in which the sustain discharge has occurred.
A negative wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5, and a positive wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5. Thereafter, the sustain pulse voltage returns to 0 (V). Subsequently, when a positive sustain pulse voltage Vm (V) is applied to all the sustain electrodes SUS1 to SUSN, the surface of the protective film 3 on the scan electrode 4 and the protection on the sustain electrode 5 in the discharge cells 12 in which the sustain discharge has occurred. The voltage applied to the surface of the film 3 is the sustain pulse voltage Vm (V)
To the sum of the negative wall voltage of the surface of the protective film 3 on the scan electrode 4 accumulated by the immediately preceding sustain discharge and the positive wall voltage of the surface of the protective film 3 on the sustain electrode 5. Become. For this reason, the discharge cell 12 which has just generated the sustain discharge
, A sustain discharge occurs between the scan electrode 4 and the sustain electrode 5, and a positive wall voltage is accumulated on the surface of the protective film 3 on the scan electrode 4 in the discharge cell 12 in which the sustain discharge has occurred. Negative wall voltage is accumulated on the surface of the protective film 3 on 5. Thereafter, the sustain pulse voltage returns to 0 (V).
Thereafter, similarly, the sustain discharge is continuously performed by alternately applying the positive sustain pulse voltage Vm (V) to all the scan electrodes SCN1 to SCNN and all the sustain electrodes SUS1 to SUSN.

The pulse width of the last sustain pulse voltage applied during the sustain period is set to be shorter than the time when the discharge forms a wall voltage and stably ends. The voltage of the electrodes SCN1 to SCNN and the sustain electrodes SUS1 to SUSN is a constant voltage Vh
(V). Therefore, the scanning electrode SCN1
To the wall voltage of the surface of the protective film 3 on the SCNN and the sustain electrode SU
The wall voltage on the surface of the protective film 3 on S1 to SUSN becomes substantially equal, and the erasing operation is performed. Such a sustain discharge does not occur in the discharge cells 12 in which no write discharge has occurred.

Next, the initialization period overlapping the sustain period will be described below. In the period before the initialization period, the voltage between all the scan electrodes SCN1 to SCNN and all the data electrodes D1 to DM is 0 (V) or Vm.
(V). Here, the voltage applied between the surface of the insulator layer 7 on the data electrode 8 and the surface of the protective film 3 on the scan electrode 4 in the discharge cell 12 in which the writing discharge has occurred is V at maximum.
m (V) and the positive wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4 are added to the negative wall accumulated on the surface of the insulator layer 7 on the data electrode 8 by the writing operation. This is the sum of the absolute values of the voltages, which exceeds the discharge starting voltage. Therefore, the discharge cell 1 in which the write discharge has occurred
In 2, discharge occurs from the scan electrode 4 to the data electrode 8. This is the initialization discharge for the data electrode 8, and a positive wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode 8. The setup discharge occurs every time the sustain pulse voltage is applied during a period before the setup period.

On the other hand, in the discharge cell 12 in which no write discharge is performed, the voltage between the surface of the insulating layer 7 on the data electrode 8 and the surface of the protective film 3 on the scan electrode 4 is V at maximum.
The positive wall voltage accumulated on the surface of the insulator layer 7 on the data electrode 8 is subtracted from the sum of m (V) and the positive wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4. This does not exceed the firing voltage. Therefore, the discharge cells 12 that have not performed the write discharge in the previous subfield
In the period before the initializing period, the initializing discharge to the data electrode 8 does not occur.

Next, the period after the initialization period will be described below. In the initialization operation in the period after the initialization period,
First, a positive voltage Vh (V) is applied to all sustain electrodes SUS1 to SUSN and all scan electrodes SCN1 to SCNN, respectively. Further, all the scan electrodes SCN1 to SCNN have ramps that gradually decrease from the voltage Vh (V) which is lower than the discharge start voltage to the voltage Ve (V) which is higher than the discharge start voltage for all the sustain electrodes SUS1 to SUSN. Apply voltage. In the discharge cells 12 in which the setup discharge has occurred during the period before the setup period while the lamp voltage is falling, the setup discharge is generated again from the sustain electrode 5 to the scan electrode 4. This is because the voltage between the surface of the protective film 3 on the sustain electrode 5 and the surface of the protective film 3 on the scan electrode 4 in the discharge cell 12 where the setup discharge has occurred in the period before the setup period is:
The positive voltage Vh (V) applied to the sustain electrode 5 and the positive wall voltage accumulated on the surface of the protective film 3 on the sustain electrode 5 by the initializing discharge and the surface of the protective film 3 on the scan electrode 4 This is because the falling ramp voltage is added to the sum of the negative wall voltage accumulated in the discharge lamp and the discharge start voltage. This initializing discharge is weak,
A positive wall voltage slightly accumulates on the surface of the protective film 3 on the scan electrode 4, and a negative wall voltage slightly accumulates on the surface of the protective film 3 on the sustain electrode 5. Further, a weak discharge also occurs between the data electrode 8 and the scanning electrode 4, and the positive wall voltage accumulated on the surface of the insulating layer 7 on the data electrode 8 is adjusted to a value suitable for the writing operation. . Regarding the discharge cells 12 in which the first initializing discharge has not occurred in the period before the initializing period, the discharge cells 12 have already been adjusted to a value suitable for the writing operation in the previous subfield. The second reset discharge does not occur. Thus, the maintenance operation and the initialization operation in the initialization period including the maintenance period are completed.

[0017]

However, in the initialization operation in the above-described conventional driving method, the discharge cells that have not performed the write discharge are stored in the column electrodes during the period before the initialization period including the sustain period. The positive wall voltage and the negative wall voltage accumulated in the first row electrode may be weakened. In this case, there is a problem that a normal initialization operation is not performed in a period after the initialization period. As a result, there is a problem that when a write operation is actually performed, the wall voltage is weakened to a state where a normal write operation cannot be performed.

According to the present invention, a discharge cell in which a write discharge has not been performed has a positive wall voltage and a first row voltage accumulated in a column electrode before a reset period including a sustain period. Even if the negative wall voltage accumulated in the electrode is weakened, the weakened wall voltage is returned to a normal state, and the initialization operation and the subsequent write operation in the period after the initialization period can be performed normally. It is an object of the present invention to provide an initialization operation method that can be performed.

[0019]

In order to solve the above problems, one field of the present invention is composed of a plurality of subfields including an initialization period, a writing period, and a sustain period, and includes a first row electrode and a first row electrode. The method for driving a plasma display in which two row electrodes and column electrodes are formed includes applying a first voltage pulse exceeding a firing voltage to the column electrodes to the first row electrodes after the sustain operation in the sustain period. It is characterized by doing.

Further, the first voltage pulse is higher than the discharge starting voltage for the column electrode and lower than the discharge starting voltage for the second row electrode.

Further, the second row electrode is applied to the first row electrode.
The one voltage pulse is a ramp voltage that changes from a voltage lower than the discharge start voltage to a voltage higher than the discharge start voltage with respect to the column electrode. Further, the rate of change of the lamp voltage pulse is 2 V / μsec or less.

The second row electrode applied to the first row electrode
The one voltage pulse is a voltage pulse that changes exponentially from a voltage lower than the discharge start voltage to a voltage higher than the discharge start voltage with respect to the column electrode. The time constant for determining the exponentially changing voltage pulse is not more than 20 μ.

Further, the first voltage pulse is applied within 10 μsec after the application of the last sustain voltage pulse in the sustain period. Further, the width of the first voltage pulse is within 10 μsec.

Thus, if no write discharge is performed immediately before the initialization period in the preceding period of the initialization period including the sustain period, the positive wall voltage stored in the column electrode and the first row electrode are stored. Even if each of the applied negative wall voltages is weakened, a normal initialization operation can be performed in a period after the initialization period, and a wall voltage effectively acting on the writing operation can be accumulated in each electrode. .

Further, the second voltage pulse is applied to the second row electrode for at least a period including a period in which the first voltage pulse is applied to the first row electrode. Further, the second voltage pulse is lower than the firing voltage for the first row electrode and the first column electrode.

[0026] This makes it possible to more reliably avoid post-discharge that may occur between the first row electrode and the second row electrode when the first voltage pulse is applied to the first row electrode.

Further, the second voltage pulse applied to the second row electrode is a ramp voltage that changes from a voltage lower than a discharge start voltage to a voltage higher than a discharge start voltage with respect to the column electrode. It is characterized by. In addition, the first
The rate of change of the ramp voltage pulse applied to the row electrode is 1 V /
It is characterized in that it is less than μ seconds.

Further, the second voltage pulse applied to the second row electrode is a voltage pulse which changes exponentially from a voltage lower than a discharge start voltage to a voltage higher than a discharge start voltage with respect to the column electrode. It is characterized by. Further, a time constant for determining an exponentially changing voltage pulse to be applied to the first row electrode is 40 μm or less.

Thus, even when an erroneous discharge occurs between the second row electrode and the column electrode when the second voltage pulse is applied to the second row electrode, the discharge is weakened. And a decrease in contrast can be suppressed.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a driving method according to a first aspect of the present invention, one field is composed of a plurality of subfields including an initialization period, a writing period, and a sustaining period. A method for driving a plasma display in which a row electrode and a column electrode are formed, wherein after a sustaining operation in the sustaining period, a first voltage pulse exceeding a firing voltage for the column electrode is applied to the first row electrode. Is applied to the plasma display panel. The first voltage pulse is higher than the discharge start voltage for the column electrode and is lower than the discharge start voltage for the second row electrode. As a result, when no write discharge occurred between the first row electrode and the column electrode, the wall voltage accumulated in the first row electrode and the column electrode in the write period and the subsequent sustain period was weakened. Even in this case, a discharge can be performed again between the first row electrode and the column electrode, and as a result, a normal setup discharge can be performed in a period after the setup period. In addition, a normal writing operation can be performed in a subsequent writing period. Further, if the wall voltage accumulated in the first row electrode and the column electrode is not reduced to a normal value during the writing period and the subsequent sustain period, the first voltage applied to the first row electrode The pulse does not cause a discharge again between the first row electrode and the column electrode. Further, depending on the voltage value of the first voltage pulse, even if the wall voltage accumulated in the first row electrode and the column electrode is not reduced to a normal value during the writing period and the subsequent sustain period, the first A discharge may occur again between the first row electrode and the column electrode due to the voltage pulse. In this case, the downstream ramp discharge in the period after the initialization period effectively affects the write operation in the subsequent write period. Wall voltage can be stored in each electrode.

The driving method according to claim 3 of the present invention is the first method.
A first voltage pulse applied to one of the row electrodes is a ramp voltage that changes from a voltage lower than or equal to a discharge start voltage to a voltage higher than the discharge start voltage with respect to a column electrode. It is. This makes it possible to apply the first voltage pulse while gradually changing it, to avoid a discharge accompanied by a large light emission by applying the first voltage pulse, and to perform a weak discharge without a large light emission. Can be. Further, erroneous discharge that can be generated by applying the first voltage pulse can be avoided, and a stable initialization operation can be performed.
Further, the circuit used for the initialization operation performed at the beginning of the field can be shared, so that the circuit cost can be reduced. In addition, it is preferable to apply the lamp voltage for a sufficient time to perform stable discharge without erroneous discharge. Therefore, the rate of change of the first ramp voltage pulse applied to the first row electrode is preferably the value described in claim 4.

The driving method according to claim 5 of the present invention is the first method.
Wherein the first voltage pulse applied to the row electrodes is a voltage pulse that changes exponentially from a voltage lower than the firing voltage to a voltage higher than the firing voltage with respect to the column electrodes. It is a driving method. This makes it possible to apply the first voltage pulse while changing it more gently at a voltage at which a discharge can actually occur, and to avoid a discharge accompanied by a large light emission due to the application of the first voltage pulse. Weak discharge can be performed. In addition, erroneous discharge that can be generated by applying the first voltage pulse can be avoided at the same time, and a stable initialization operation can be performed. Also,
The circuit configuration is simpler than the lamp voltage, and the circuit cost can be reduced. Further, it is preferable to apply the voltage over a sufficient time in order to perform stable discharge without erroneous discharge. Therefore, the time constant for determining the first voltage pulse applied to the first row electrode is preferably the value described in claim 6.

The first voltage pulse is generated by applying the last sustain pulse voltage of the sustain operation in the previous sustain period, and thereafter, the wall voltage accumulated in the first row electrode and the second row electrode, respectively. The expected effect can be obtained by applying the voltage after a period sufficient for stabilization. Further, if there is a period in which the wall voltage is sufficiently stabilized, the effect does not change even if the period is further extended. Therefore, it is preferable that the first voltage pulse be applied within the value described in claim 7 after the last sustain pulse voltage is applied. In addition, by applying the first voltage pulse, a discharge is caused between the first row electrode and the column electrode, and a wall voltage is accumulated in each electrode so that the subsequent initialization operation can be performed normally. There is a need. Therefore, it is preferable that the first voltage pulse is applied during a period in which the wall voltage is sufficiently stably accumulated. Even if the voltage is applied for a period sufficient for the wall voltage to be stably accumulated, the effect does not change. Therefore, it is preferable that the width of the first voltage pulse is the value described in claim 8.

The driving method according to claim 9 of the present invention is characterized in that the second voltage pulse is applied for at least a period including a period in which the first voltage pulse is applied to the first row electrode to the second row electrode. Is applied to the plasma display panel. The second voltage pulse is set to a voltage equal to or lower than the discharge starting voltage for the first row electrode and the column electrode. This makes it possible to more reliably avoid a discharge that may occur between the first row electrode and the second row electrode when the first voltage is applied to the first row electrode.

Further, the second voltage pulse is set to a ramp voltage that gradually rises, and the second voltage pulse is applied, so that the second row electrode and the column electrode and the second row electrode and the first row electrode are connected to each other. Even when the voltage between the row electrode and the row electrode exceeds the discharge starting voltage, a weak discharge can be performed, and a discharge accompanied by large light emission can be avoided. As a result, even when an erroneous discharge occurs, a decrease in contrast can be suppressed. Further, it is preferable to apply the lamp voltage for a sufficient time in order to stably perform a weak erroneous discharge. Therefore, the rate of change of the second ramp voltage pulse applied to the second row electrode is preferably the value described in claim 12.

Further, the second voltage pulse is changed to an exponentially changing voltage pulse, and the second voltage pulse is applied, so that the second row electrode and the column electrode and the second row electrode are connected to each other. Even when the voltage between the first row electrode and the first row electrode exceeds the discharge starting voltage, a weak discharge can be performed, and a discharge accompanied by a large light emission can be avoided. As a result, even when an erroneous discharge occurs, a decrease in contrast can be suppressed. Also,
The circuit configuration is simpler than the lamp voltage, and the circuit cost can be reduced. Further, it is preferable to apply the voltage for a sufficient time in order to stably perform a weak erroneous discharge. Therefore, the time constant for determining the second voltage pulse applied to the second row electrode is preferably the value described in claim 14.

(Embodiment 1) FIG. 7 shows a configuration diagram of a plasma display device according to Embodiment 1 of the present invention.
Hereinafter, an initialization operation in driving the plasma display of the present invention will be described.

The plasma display device shown in FIG. 7 has a plasma display panel 100 and a data driver 20.
0, a scan driver 300 and a sustain driver 400 are additionally provided.

The plasma display panel 100 includes a plurality of data electrodes 8, a plurality of scan electrodes 4, and a plurality of sustain electrodes 5. The plurality of data electrodes 8 are arranged in the vertical direction of the screen, and the plurality of scan electrodes 4 and the plurality of sustain electrodes 5 are arranged in the horizontal direction of the screen. The plurality of sustain electrodes 5 are commonly connected. At each intersection of the data electrode 8, the scan electrode 4, and the sustain electrode 5, a discharge cell 12 is provided, and each discharge cell 12 forms a pixel on a screen. The details of the electrode arrangement of the plasma display are the same as those of the conventional plasma display shown in FIG.

The data driver 200 is connected to the plurality of data electrodes 8 of the plasma display panel 100. The scan driver 300 is connected to the plurality of scan electrodes 4 of the plasma display panel 100. The sustain driver 400 is connected to the plurality of sustain electrodes 5 of the plasma display panel 100. The scan driver 300 applies a plurality of scan electrodes 4 to each of the plurality of scan electrodes 4 in the initialization period and the write period including the sustain period of each subfield so that the sustain discharge, the initialization discharge, and the write discharge can be stably performed in all the discharge cells 12. A pulse for a maintenance operation, a pulse for an initialization operation, and a pulse for a write operation are applied. In addition, the sustain driver 400 performs a plurality of sustain electrodes 5 in the initialization period and the write period including the sustain period of each subfield so that the sustain discharge, the initialization discharge, and the write discharge can be stably performed in all the discharge cells 12. , A pulse for a maintenance operation, a pulse for an initialization operation, and a pulse for a write operation are applied. The data driver 20
0 applies a write voltage pulse that is turned on or off in accordance with video signals input to the plurality of data electrodes 8 during a write period of each subfield so that a stable write discharge can be performed in all the discharge cells 12. . Thus, the sustain operation, the initialization operation, and the write operation are performed in the predetermined discharge cell 12.

FIGS. 1, 2 and 3 show the application of driving voltages to the scan electrode 4, the sustain electrode 5, and the data electrode 8 during the sustaining operation, the initialization operation, and the writing operation in driving the plasma display panel 100 of FIG. An example of the timing is shown.

The operation in the initialization period and the writing period at the beginning of the field is the same as the operation described in the conventional example, and therefore the wall voltage accumulated in each electrode by the operation in each period is also the same.

Referring to FIG. 1, a description will be given of a sustaining operation in a period where the sustaining period overlaps with the initializing period in the initializing period including the sustaining period in each subfield. Assuming that this is a period before the initialization period, as shown in FIG. 1, the sustain pulse voltage Vm (V) is alternately applied to all the scan electrodes 4 and all the sustain electrodes 5 in the previous period. Next, the maintenance operation in the preceding period will be described below. First, all the scan electrodes 4 and the sustain electrodes 5 are set to 0.
(V), when a positive sustain pulse voltage Vm (V) is applied to all the scan electrodes 4, the surface of the protective film 3 on the scan electrodes 4 and the sustain electrodes 5 in the discharge cells 12 in which the write discharge has occurred. The voltage between the surface of the upper protective film 3 and the sustaining pulse voltage Vm (V) corresponds to the positive wall voltage of the protective film 3 on the scan electrode 4 and the protective film on the sustain electrode 5 accumulated during the writing period. The sum of the negative wall voltages accumulated on the surface of No. 3 exceeds the firing voltage. Therefore, a sustain discharge occurs between the scan electrode 4 and the sustain electrode 5 in the discharge cell 12 in which the write discharge has occurred, and the surface of the protective film 3 on the scan electrode 4 in the discharge cell 12 in which the sustain discharge has occurred. , A negative wall voltage is accumulated, and a positive wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5. Thereafter, the sustain pulse voltage returns to 0 (V). Subsequently, when a positive sustain pulse voltage Vm (V) is applied to all the sustain electrodes 5, the surface of the protective film 3 on the scan electrodes 4 and the protective film 3 on the sustain electrodes 5 in the discharge cells 12 in which the sustain discharge has occurred. Of the protective film 3 on the scan electrode 4 accumulated by the immediately preceding sustain discharge to the sustain pulse voltage Vm (V).
And the positive wall voltage accumulated on the surface of the protective film 3 on the sustain electrode 5 is added. Therefore, a sustain discharge occurs between scan electrode 4 and sustain electrode 5 in discharge cell 12 in which the sustain discharge has occurred immediately before, and protective film 3 on scan electrode 4 in discharge cell 12 in which the sustain discharge has occurred. Positive wall voltage accumulates on the surface,
A negative wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5. Thereafter, the sustain pulse voltage returns to 0 (V). Thereafter, similarly, the sustain discharge is continuously performed by alternately applying the positive sustain pulse voltage Vm (V) to all the scan electrodes 4 and all the sustain electrodes 5.

The pulse width of the last sustain pulse voltage applied in the sustain period is set to be shorter than the time when the discharge forms a wall voltage and stably ends. The voltage of electrode 4 and sustain electrode 5 is set to a constant voltage Vh (V). For this reason, the wall voltage on the surface of the protective film 3 on the scan electrode 4 is substantially equal to the wall voltage on the surface of the protective film 3 on the sustain electrode 5, and an erasing operation is performed. Such a sustain discharge does not occur in the discharge cells 12 in which no write discharge has occurred.

Next, the initialization operation in the initialization period overlapping with the sustain period will be described below. In the period before the initialization period, all scan electrodes 4 and all data electrodes 8
Is 0 (V) or Vm (V). Here, the surface of the insulator layer 7 on the data electrode 8 and the protective film 3 on the scan electrode 4 in the discharge cell 12 in which the write discharge occurred.
Applied to the surface of the insulating layer 7 on the data electrode 8 is the sum of Vm (V) at the maximum and the positive wall voltage accumulated on the surface of the protective film 3 on the scanning electrode 4. To the absolute value of the negative wall voltage accumulated by the writing operation, which exceeds the discharge starting voltage. Therefore, in the discharge cell 12 in which the write discharge has occurred, a discharge occurs from the scan electrode 4 toward the data electrode 8. This is the initialization discharge for the data electrode 8, and a positive wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode 8. The setup discharge occurs every time the sustain pulse voltage is applied during a period before the setup period.

On the other hand, in the discharge cell 12 in which no write discharge is performed, the voltage between the surface of the insulating layer 7 on the data electrode 8 and the surface of the protective film 3 on the scan electrode 4 is V at maximum.
The positive wall voltage accumulated on the surface of the insulator layer 7 on the data electrode 8 is subtracted from the sum of m (V) and the positive wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4. This does not exceed the firing voltage. Therefore, the discharge cells 12 that have not performed the write discharge in the previous subfield
In the period before the initializing period, the initializing discharge to the data electrode 8 does not occur.

Subsequently, a period in which the sustain period and the initialization period do not overlap will be described below. Assuming that this is a period after the initialization period, as shown in FIG. 1, while the positive voltage Vh (V) is applied to all the sustain electrodes 5 and the data electrodes 8 are held at 0 (V), Then, a voltage pulse of the voltage Vr (V) is applied to all the scanning electrodes 4. At this time, if the write discharge has not been performed prior to the sustain period, that is, if the sustain operation has not been performed, the surface of the protective film 3 on the scan electrode 4 in the predetermined discharge cell 12 by the initialization operation in the previous subfield. , A weakened positive wall voltage on the surface of the protective film 3 on the sustain electrode 5, and a positive wall voltage on the surface of the insulator layer 7 on the data electrode 8. Are accumulated respectively.
Here, if these wall voltages are not weakened at all during the writing period and the sustaining period, no discharge occurs between the electrodes even when the voltage Vr (V) is applied to the scanning electrodes 4. However, when the wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4 and the surface of the insulator layer 7 on the data electrode 8 during the writing period and the sustain period is weakened over time, the conventional driving method is used. Even when a ramp voltage that gradually decreases is applied to the scan electrode 4 in the initialization operation in the later period of the initialization period, the initialization discharge does not occur between the data electrode 8 and the scan electrode 4, so that the subsequent It is not possible to accumulate the necessary wall voltage for performing the writing operation normally in the writing period. Here, when the voltage Vr (V) is applied before the ramp voltage that gradually decreases is applied to the scan electrode 4, the surface of the protective film 3 on the scan electrode 4 and the insulation on the data electrode 8 during the writing period and the sustain period. Even when the wall voltage accumulated on the surface of the body layer 7 is weakened over time, the voltage between the scan electrode 4 and the data electrode 8 remains on the surface of the protective film 3 on the scan electrode 4. The voltage Vr (V) is added to the negative wall voltage and the positive wall voltage left on the surface of the insulator layer 7 on the data electrode 8, which exceeds the discharge starting voltage. Therefore, between the scan electrode 4 and the data electrode 8, the wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4 and on the surface of the insulator layer 7 on the data electrode 8 is used for a write operation in a subsequent write period. An initializing discharge occurs to make the wall voltage effective. Also, if the write discharge has been performed before the sustain period, that is, if the sustain operation has been performed in the previous period, the surface of the protective film 3 on the scan electrode 4 and the protection on the sustain electrode 5 in the predetermined discharge cell 12 will be described. Almost the same wall voltage is accumulated on the surface of the film 3, and a positive wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode 8.
In this case, even if the voltage Vr (V) is applied to the scanning electrode 4, no discharge occurs between the electrodes.

The voltage Vr applied to the scanning electrode 4
The same effect can be obtained even if (V) is a ramp voltage that gradually rises from Vm (V) as shown in FIG. Further, by setting the lamp voltage, erroneous discharge hardly occurs between the data electrode 8 and the scanning electrode 4 when the voltage Vr (V) is applied, and the discharge is weak and does not accompany large light emission. . Therefore, the initialization operation can be performed more stably than in the case where a square voltage as shown in FIG. 1 is applied, and the decrease in contrast can be suppressed. Further, since the circuit used for the initialization operation performed at the beginning of the field can be shared, the circuit cost can be reduced.

The voltage Vr applied to the scanning electrode 4
The same effect can be obtained even if (V) is a voltage pulse that rises exponentially from Vm (V) and Vh (V) as shown in FIG. Accordingly, the voltage Vr (V) can be applied while changing it more gently at a voltage at which discharge can actually occur, and a discharge accompanying large light emission due to the application of the voltage Vr (V) can be avoided, and the contrast can be reduced. Reduction can be suppressed. In addition, erroneous discharge that can be generated by applying the voltage Vr (V) can be avoided at the same time, and a stable initialization operation can be performed. Further, the circuit configuration is simpler than the lamp voltage, and the circuit cost can be reduced.

Here, the voltage Vr applied to the scanning electrode 4
(V) is applied after a sufficient time has elapsed since the last sustain pulse voltage was applied. By doing so, when the write discharge is performed, when all the scan electrodes 4 and all the sustain electrodes 5 are maintained at Vh (V) after the last sustain operation, the wall voltage on each electrode is stably maintained. Can be accumulated. In addition, when the wall voltage on each electrode is stably accumulated, the effect does not change even if a longer time elapses, so that the voltage Vr (V) is 10 μsec after the last sustain pulse voltage is applied. It is preferable to apply within. Also,
When the wall voltage accumulated on the surface of the insulator layer 7 on the data electrode 8 and the surface of the protective film 3 on the scan electrode 4 during the writing period and the sustain period is weakened, the voltage Vr (V) is changed to the voltage of the subsequent writing. It is preferable to apply the wall voltage effective for the writing operation in the period for a time necessary to accumulate in each electrode. Further, after the wall voltage effective for the writing operation in the subsequent writing period is accumulated in each electrode, even if the voltage Vr (V) is applied for a longer time, the effect does not change.
r (V) is preferably applied for a time within 100 μm. As a result, the wall voltage accumulated on the surface of the insulator layer 7 on the data electrode 8 and the surface of the protective film 3 on the scan electrode 4 required for the write discharge during the initialization period including the write period and the sustain period is reduced in time. Even if it is weakened with the passage of time, the wall voltage effectively acting on the write operation in the subsequent write period can be accumulated again.

(Embodiment 2) FIG. 7 shows a configuration diagram of a plasma display device according to Embodiment 2 of the present invention.
Hereinafter, an initialization operation in driving the plasma display of the present invention will be described. 4, 5, and 6,
FIG. 8 shows an example of the timing of applying a drive voltage to the scan electrode 4, the sustain electrode 5, and the data electrode 8 during a sustain operation, an initialization operation, and a write operation in driving the plasma display panel 100 of FIG.

The operation in the initialization period and the writing period at the beginning of the field is the same as the operation described in the conventional example, and therefore the wall voltage accumulated in each electrode by the operation in each period is also the same.

The initialization operation in the initialization period including the sustain period in each subfield will be described below. The period before the initializing period in which the sustaining period and the initializing period overlap is the same as in the first embodiment of the present invention, and will not be described. The period after the initialization period will be described below with reference to FIG. While the positive voltage Vh (V) is applied to all the sustain electrodes 5 and all the data electrodes 8 are maintained at 0 (V), a voltage pulse of the voltage Vr (V) is applied to all the scan electrodes 4. Apply. At this time, a voltage pulse of voltage Vs (V) is applied to all sustain electrodes 5 simultaneously with voltage Vr (V). At this time, if the write discharge has not been performed prior to the sustain period, that is, if the sustain operation has not been performed, the surface of the protective film 3 on the scan electrode 4 in the predetermined discharge cell 12 by the initialization operation in the previous subfield. , A weakened positive wall voltage on the surface of the protective film 3 on the sustain electrode 5, and a positive wall voltage on the surface of the insulator layer 7 on the data electrode 8. Are accumulated respectively. Here, if these wall voltages are not weakened at all during the writing period and the sustain period, the voltage Vr (V) is applied to the scan electrode 4 and the voltage Vs is applied to the sustain electrode 5.
Even when (V) is applied, no discharge occurs between the electrodes. However, when the wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4 and the surface of the insulator layer 7 on the data electrode 8 during the writing period and the sustain period is weakened over time, the conventional driving method is used. In the initializing operation in the later period of the initializing period, even when a ramp voltage that gradually decreases is applied to the scan electrode 4, the initializing discharge does not occur between the data electrode 8 and the scan electrode 4. It is not possible to accumulate the necessary wall voltage for performing the writing operation normally in the writing period. Here, the voltage Vr (V) is applied to the scan electrode 4 and the voltage Vs is applied to the sustain electrode 5 before the ramp voltage that gradually decreases is applied to the scan electrode 4.
When (V) is applied, the wall voltage accumulated on the surface of the protective film 3 on the scan electrode 4 and the surface of the insulator layer 7 on the data electrode 8 during the writing period and the sustain period, respectively, with time. Even when weakened, the voltage between the scan electrode 4 and the data electrode 8 remains on the surface of the protective layer 3 on the scan electrode 4 and on the surface of the insulator layer 8 on the data electrode 8. And the voltage Vr (V) is added to the wall voltage. Since this exceeds the discharge starting voltage, the scanning electrode 4
The wall voltage accumulated between the surface of the protective film 3 on the scan electrode 4 and the surface of the insulator layer 7 on the data electrode 8 between the scan electrode 4 and the data electrode 8 effectively acts on the write operation in the subsequent write period. An initializing discharge for generating a wall voltage occurs. In addition, since voltage Vs (V) is applied to sustain electrode 5, erroneous discharge that can occur between sustain electrode 5 and scan electrode 4 can be prevented. At this time, it is considered that an erroneous discharge occurs between the sustain electrode 5 and the data electrode 8 by applying the voltage Vs (V), and the erroneous discharge causes a positive surface on the surface of the insulator layer 7 on the data electrode 8. The wall voltage and the negative wall voltage are accumulated on the surface of the protective film 3 on the sustain electrode 5, but the initializing discharge using the downstream ramp voltage applied to the scan electrode 4 in the subsequent writing period It is adjusted to a wall voltage that effectively affects the write operation.

When the write discharge has been performed prior to the sustain period, that is, when the sustain operation has been performed in the previous period, the scan electrode 4 in the predetermined discharge cell 12
Almost the same wall voltage is accumulated on the surface of the upper protective film 3 and the surface of the protective film 3 on the sustain electrode 5, and the positive wall voltage is applied on the surface of the insulator layer 7 on the data electrode 8. Has been accumulated. In this case, even if the voltage Vr (V) is applied to the scan electrode 4 and the voltage Vs (V) is applied to the sustain electrode 5, no discharge occurs between the electrodes.

The voltage Vs applied to the sustain electrode 5
By setting (V) to a ramp voltage that gradually rises from Vh (V) as shown in FIG. 5, an error that may occur between the sustain electrode 5 and the data electrode 8 by applying the voltage Vs (V). The discharge can be made weaker than the discharge. Due to this weak discharge, a positive wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode 8 and a negative wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5. By the initialization discharge using the applied downward ramp voltage, the voltage is adjusted to a wall voltage that effectively acts on the writing operation in the subsequent writing period. Therefore, even when an erroneous discharge occurs as compared with the case where a square voltage is applied, the discharge can be weakened and a decrease in contrast can be suppressed. Further, it can be expected that a similar effect can be obtained with respect to an erroneous discharge that can occur between the sustain electrode 5 and the scan electrode 4.

The voltage Vs applied to the scanning electrode 4
By making (V) a voltage pulse that rises exponentially from Vh (V) as shown in FIG. 6, by applying the voltage Vs (V) in the same manner as when applying the lamp voltage, the sustain electrode 5 The erroneous discharge that may occur between the data electrode 8 and the data electrode 8 can be weakened. Therefore, similarly, a decrease in contrast can be suppressed. Due to this weak discharge, a positive wall voltage is accumulated on the surface of the insulator layer 7 on the data electrode 8 and a negative wall voltage is accumulated on the surface of the protective film 3 on the sustain electrode 5. By the initialization discharge using the applied downward ramp voltage, the voltage is adjusted to a wall voltage that effectively acts on the writing operation in the subsequent writing period. In addition, the sustain electrode 5 and the scan electrode 4
It can be expected that a similar effect can be obtained even with respect to erroneous discharge that can occur between the above. Further, since the voltage Vs (V) is a voltage pulse that changes exponentially, the circuit configuration can be simplified and the circuit cost can be reduced as compared with the lamp voltage.

[0057]

As described above, the present invention relates to the driving of a plasma display, and is an initialization operation in an initialization period including a sustain period in which a wall voltage effectively acting on a write operation in a write period is accumulated in each electrode. Yes, even if the wall voltage accumulated on the data electrode and the scan electrode during the writing period and the sustain period is weakened, the weakened wall voltage is applied to the writing operation in the subsequent writing period by applying a voltage pulse to the scanning electrode. The wall voltage can work effectively, and a normal write operation can be performed.

[Brief description of the drawings]

FIG. 1 is a drive voltage and operation timing chart applied to a scan electrode, a sustain electrode, and a data electrode during an initialization period including a sustain period and a subsequent write period according to the first embodiment of the present invention.

FIG. 2 is a diagram illustrating a drive voltage applied to a scan electrode, a sustain electrode, and a data electrode when a ramp voltage is used for an initialization operation in a reset period including a sustain period and a subsequent write period according to the first embodiment of the present invention; And operation timing chart

FIG. 3 illustrates a scan electrode, a sustain electrode, and a data electrode in a case where a voltage pulse that changes exponentially is used for an initialization operation in an initialization period including a sustain period and a subsequent writing period according to the first embodiment of the present invention. Voltage and operation timing chart

FIG. 4 is a drive voltage and operation timing chart applied to a scan electrode, a sustain electrode, and a data electrode during an initialization period including a sustain period and a subsequent write period according to the second embodiment of the present invention.

FIG. 5 shows a drive voltage applied to a scan electrode, a sustain electrode, and a data electrode when a ramp voltage is used for an initialization operation in a reset period including a sustain period and a subsequent write period according to the second embodiment of the present invention. And operation timing chart

FIG. 6 illustrates a scan electrode, a sustain electrode, and a data electrode in the case where a voltage pulse that changes exponentially is used for an initialization operation in an initialization period including a sustain period and a subsequent writing period according to the first embodiment of the present invention. Voltage and operation timing chart

FIG. 7 is a schematic diagram of a plasma display device.

FIG. 8 is a partial perspective view of a plasma display panel.

FIG. 9 is an electrode arrangement diagram of a plasma display panel.

FIG. 10 is a configuration diagram of a driving timetable of a conventional plasma display.

And FIG. 11 is a diagram illustrating driving voltages applied to scanning electrodes, sustaining electrodes, and data electrodes in a conventional plasma display and operation timings.

FIG. 12 is a drive voltage and operation timing chart applied to a scan electrode, a sustain electrode, and a data electrode during an initialization period including a sustain period and a subsequent write period in a conventional plasma display.

[Explanation of symbols]

 Reference Signs List 4 scan electrode 5 sustain electrode 8 data electrode 12 discharge cell 100 plasma display panel 200 data driver 300 scan driver 400 sustain driver

Claims (14)

[Claims] 1. One field is composed of a plurality of subfields including an initialization period, a writing period, and a sustain period, and drives a plasma display in which a first row electrode, a second row electrode, and a column electrode are formed. A method of driving a plasma display panel, comprising: applying a first voltage pulse exceeding a firing voltage to a column electrode to a first row electrode after a sustain operation in the sustain period. 2. The driving method according to claim 1, wherein the first voltage pulse exceeds a discharge starting voltage for the column electrode and is lower than a discharge starting voltage for the second row electrode. . 3. The method according to claim 1, wherein the first voltage pulse applied to the first row electrode is a ramp voltage that changes from a voltage lower than a discharge start voltage to a voltage higher than a discharge start voltage with respect to the column electrode. The driving method according to claim 1, wherein: 4. The driving method according to claim 3, wherein the rate of change of the ramp voltage pulse applied to the first row electrode is 2 V / μsec or less. 5. The method according to claim 1, wherein the first voltage pulse applied to the first row electrode is a voltage pulse that changes exponentially from a voltage lower than a discharge start voltage to a voltage higher than a discharge start voltage with respect to the column electrode. The driving method according to claim 1, wherein: 6. The driving method according to claim 5, wherein a time constant for determining an exponentially changing voltage pulse applied to the first row electrode is 20 μ or less. 7. The driving method according to claim 1, wherein the first voltage pulse is applied within 10 μsec after application of a last sustain voltage pulse in the sustain period. 8. The driving method according to claim 1, wherein the width of the first voltage pulse is within 100 μsec. 9. The method according to claim 1, wherein the second voltage pulse is applied to the second row electrode for a period including at least a period in which the first voltage pulse is applied to the first row electrode. 1. The driving method according to 1. 10. The driving method according to claim 9, wherein the first voltage pulse is lower than a discharge starting voltage for the first row electrode and the first column electrode. 11. The driving method according to claim 9, wherein the second voltage pulse is a ramp voltage. 12. The driving method according to claim 11, wherein a rate of change of a ramp voltage pulse applied to the first row electrode is 1 V / μsec or less. 13. The driving method according to claim 9, wherein the second voltage pulse is an exponentially changing voltage pulse. 14. A driving method according to claim 13, wherein a time constant for determining an exponentially changing voltage pulse to be applied to said first row electrode is 40 μ or less.