JP2002006799A - Method for driving plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a stability of discharge by securing stable and continuous sustained discharge operation for a sustaining period and to reduce a sustained pulse waveform to be applied to scanning electrodes and sustaining electrodes for the sustaining period in a method for driving a plasma display panel. SOLUTION: A stability of discharge is improved by setting a high level period of a sustaining pulse waveform to be applied to the scanning electrodes and sustaining electrodes for the sustaining period to 2 μS to 5 μS, making a wall voltage fully move across the scanning electrodes and the sustaining electrodes, controlling a drop of the wall voltage associated with continuation of the sustained discharge, and securing continuous and stable operation of the sustained discharge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a plasma display panel used for displaying an image on a television receiver, a computer terminal or the like.

[0002]

2. Description of the Related Art In a conventional plasma display panel (hereinafter, referred to as a panel), a plurality of pairs of a scanning electrode 2 and a sustain electrode 3 are formed on a first glass substrate 1 as shown in FIG.
Are provided in parallel with each other, and a dielectric layer 4 covering the scan electrode 2 and the sustain electrode 3 and a protective film 5 are provided thereon. On the other hand, on the second glass substrate 6, a dielectric layer 7
A plurality of data electrodes 8 covered with a metal electrode 8 are provided between the data electrodes 8 and on the dielectric layer 7.
A partition wall 9 is provided in parallel with.

A fluorescent pair 10 is provided on the surface of the dielectric layer 7 and on the side of the partition wall 9. The first glass substrate 1 and the second glass substrate 6 are arranged to face each other with the discharge space 11 interposed therebetween so that the scanning electrodes 2 and the sustain electrodes 3 are orthogonal to the data electrodes 8.

[0004] Also, sandwiched between two adjacent partition walls 9,
A discharge cell 12 is formed at the intersection of the scan electrode 2 and the sustain electrode 3 forming a pair with the data electrode 8. Discharge space 11
Contains xenon and at least one of helium, neon and argon as a discharge gas.

The electrode arrangement of this panel has an m × n matrix configuration as shown in FIG. 6, in which m columns of data electrodes D _{1 to} D _m are arranged in the column direction and n columns in the row direction. Row scan electrodes SCN _{1 to} SCN _n and sustain electrodes SUS _{1 to} S
US _n are arranged. Further, the discharge cells 12 shown in FIG. 5 are provided in a region as shown in FIG.

FIG. 7 shows an operation timing chart of a conventional driving method for driving this panel.

FIG. 7 shows one subfield period. One field period for displaying one screen is composed of a plurality of subfield periods. Next, a conventional panel driving method will be described with reference to FIGS. 6, 7, and 8. FIG.

[0008] As shown in FIG.
In the reset operation, all the data electrodes D₁~ D_mAnd all
Sustain electrode SUS₁~ SUS_nIs maintained at 0 (V),
Scan electrodes SCN₁~ SCN_nFrom 0 (V) to everything
Sustain electrode SUS₁~ SUS_nBelow the firing voltage
Discharge starts after rapidly rising to the potential Vc (V)
Positive electrode that slowly rises to potential Vd (V) exceeding the voltage
Apply a gender initialization waveform. This initialization waveform
In the ascending process, all the runnings in the individual discharge cells 12 are performed.
Probe electrode SCN₁~ SCN_nFrom all data electrodes D₁~ D_m
And all sustain electrodes SUS₁~ SUS_nFirst weakness
Reset discharge occurs, and the scan electrode SCN ₁~ SCN_nupper
A negative wall voltage is accumulated on the surface of the protective film 5, and the data electrode D₁
~ D_mPhosphor 10 surface and sustain electrode SUS₁~ SU
S_nA positive wall voltage is accumulated on the surface of the upper protective film 5.

Next, in the initialization operation in the latter half of the initialization period,
And all sustain electrodes SUS₁~ SUS_nPotential Vq
(V) to apply all scan electrodes SCN₁~ SCN_nTo
All sustain electrodes SUS from potential Vd₁~ SUS_nAgainst
Rapidly drops to the potential Ve (V) below the discharge starting voltage
After that, gradually increase to Vi (V) exceeding the discharge starting voltage.
Then, the application of the initialization waveform is completed. This initialization wave
In the gradual descending process, the individual discharge cells 12
And all data electrodes D₁~ D_mAnd all sustain electrodes S
US₁~ SUS_nFrom all scan electrodes SCN₁~ SCN_nTo
The second weak initializing discharge occurs, and the scan electrode SCN₁
~ SCN_nNegative wall voltage on the surface of the upper protective film 5, sustain electrode S
US₁~ SUS_nPositive wall voltage on the surface of the upper protective film 5, and
Data electrode D ₁~ D_mPositive wall voltage on the surface of the upper phosphor 10
Weakened to a wall voltage suitable for subsequent write operations
It is.

Thus, the initialization operation in the initialization period is completed.

In the writing operation in the next writing period, the potential Vg (V) is applied to all the scanning electrodes SCN _{1 to} SCN _n.
It was applied to continue applying a potential Vq to all the sustain electrodes SUS ₁ ~SUS _n. Further, of the data electrodes D _{1 to} D _m , a predetermined data electrode D _j (j is an integer of _{1 to m} ) corresponding to the discharge cell 12 to be displayed on the first row has a potential having the same polarity as the initialization waveform. applies a data waveform Vb (V), to the scan electrodes SCN ₁ of the first line, applying a scan waveform of a potential Vi is the same potential as that at the end of the potential Vi of the initialization waveform in the initialization waveform and opposite polarity . In this case, the intersection of the predetermined data electrode D _j and the scanning electrode SCN ₁ (first intersection)
The potential difference between the phosphor 10 surface and the scanning electrodes SCN ₁ on the protective film 5 surface in the scanning from those positive wall voltage of the phosphor 10 surface on data electrode D _j plus the potential Vb of the data waveform since the minus the negative wall voltage of the protection layer 5 surface on the electrode SCN ₁ (i.e. those obtained by adding an absolute value), the first intersection, the predetermined data electrode D _j and the scanning electrode SCN ₁ A write discharge occurs between them. Induced simultaneously to the writing discharge, also occurs write discharge between the sustain electrode SUS ₁ and the scanning electrode SCN ₁ at the first intersection, the protective film on the scanning electrode SCN ₁ of the first intersection 5
The positive wall voltage is accumulated on the surface, and the sustain electrode S at the first intersection is
Negative wall voltage is accumulated in the protective film 5 surface on US _1.

[0012] Next, among the data electrodes D ₁ to D _m, applying a data waveform of initializing waveform of the same polarity as the potential Vb to the predetermined data electrode D _j that corresponds to the discharge cell 12 to be displayed on the second line to together, the scanning electrodes SCN ₂ of the second line, applying a scan waveform of a potential Vi is the same potential as that at the end of the potential Vi of the initialization waveform in the initialization waveform and opposite polarity. In this case, the intersection of the predetermined data electrode D _j and the scanning electrode SCN ₂ the potential difference between the phosphor 10 surface and the protective film 5 surface on the scanning electrode SCN ₂ in the (second crossing portion), the data waveform Potential V
Since the minus the negative wall voltage on data electrodes D _j on the phosphor 10 surface of the positive wall voltage protective film 5 surface on the scanning electrode SCN ₂ from plus to b, in the second intersection , write discharge occurs between the predetermined data electrode D _j and the operation electrode SCN _2. Simultaneously, this write discharge induces the sustain electrode SUS ₂ and the scan electrode S at the second intersection.
A write discharge also occurs with CN ₂ , a positive wall voltage is accumulated on the surface of the protective film 5 on the scan electrode SCN _{2 at} the second intersection, and the surface of the protective film 5 on the sustain electrode SUS _{2 at} the second intersection. , A negative wall voltage is accumulated.

A similar operation is continuously performed up to the n-th row, and the write operation in the write period ends.

In the sustain operation of the sustain period following the write period, all the S
A sustain pulse waveform having a voltage amplitude of Vh (V) is applied to CN _{1 to} SCN _n to set all the sustain electrodes SUS _{1 to} SUS _n to 0.
Hold at V.

At this time, the potential Vh of the scan electrode and the positive wall voltage of the surface of the protective film 5 on the scan electrode constituting the discharge cell are applied to the discharge cell 12 in which the write discharge has occurred. A potential is obtained by subtracting the negative wall voltage of the surface of the protective film 5 on the sustain electrode constituting the cell (that is, adding the absolute value), and a sustain discharge occurs. Due to the sustain discharge, a wall voltage is moved between the scan electrode and the surface of the protective film 5 on the sustain electrode, and a negative wall voltage is accumulated on the surface of the protective film 5 on the scan electrode constituting the discharge cell. A positive wall voltage is accumulated on the surface of the protective film 5 on the sustain electrodes constituting the discharge cells. Since the movement of the wall voltage is performed during the high level period of the sustain pulse waveform applied to the scan electrode and the sustain electrode, depending on the setting of the high level period, as shown in FIG. The wall voltage accumulated between the surfaces of the protective film 5 decreases with each sustain discharge, and it may not be possible to continuously generate a predetermined number of sustain discharges.

On the other hand, the wall voltage accumulated on the surface of the protective film 5 on the scan electrode and the sustain electrode constituting the discharge cell is weak for the discharge cell in which the write discharge has not occurred. Since only the potential Vh is applied, no sustain discharge occurs. Further, the wall voltage on the surface of the protective film 5 on the scan electrode and the sustain electrode constituting the discharge cell does not change.

In order to generate a second sustain discharge, all scan electrodes SCN _{1 to} SCN _n are maintained at 0 V, and a sustain pulse waveform having a voltage amplitude of Vh (V) is applied to all sustain electrodes SUS _{1 to} SUS _n. Is applied.

At this time, the potential Vh of the sustain electrode and the first sustain discharge are generated with respect to the discharge cell 12 which has generated the write discharge, and the positive voltage on the surface of the protective film 5 on the sustain electrode constituting the discharge cell is generated. The wall voltage is applied, and a potential obtained by subtracting the negative wall voltage on the surface of the protective film 5 on the scan electrode constituting the discharge cell is applied, and the sustain discharge is generated again. Due to the sustain discharge, a positive wall voltage is accumulated on the surface of the protective film 5 on the scan electrode constituting the discharge cell, and a negative wall voltage is accumulated on the surface of the protective film 5 on the sustain electrode constituting the discharge cell. Stored.

On the other hand, the wall voltage accumulated on the surface of the protective film 5 on the scan electrode and the sustain electrode constituting the discharge cell is weak for the discharge cell which has not caused the write discharge. Since only the potential Vh is applied, no sustain discharge occurs. Further, the wall voltage on the surface of the protective film 5 on the scan electrode and the sustain electrode constituting the discharge cell does not change.

As described above, all the scanning electrodes SCN _{1 to} SCN ₁
The potential Vh is applied to CN _n and all the sustain electrodes SUS _{1 to} SUS _n.
By alternately applying the sustain waveform (V), the sustain discharge is continuously performed in the discharge cells 12 in which the write discharge has occurred. Visible light emission from the phosphor 10 excited by ultraviolet rays generated by the sustain discharge is used for display.

[0021] In the erasing operation of the erasing period subsequent to the sustain period, applying an erase waveform that gradually rises to all the sustain electrodes SUS ₁ ~SUS _n from 0 (V) to a potential Vr (V), caused the sustain discharge In the discharge cell 12, the sustain electrode SUS _i (i is 1) while the erase waveform gradually rises.
Cause a weak erase discharge between the an integer of ~n) and scan electrode SCN _i, scan electrodes of negative protective film 5 surface on SCN _i and the wall voltage on sustain electrodes SUS _i a protective film 5 surface The positive wall voltage is weakened to stop the discharge.

Thus, the erasing operation in the erasing period is completed.

[0023]

The movement of the wall voltage between the scan electrode and the sustain electrode due to the sustain discharge in the sustain period requires a time of 2 μS to 5 μS. The high level period of the sustain pulse waveform applied to the scan electrode and the sustain electrode is 1.5 μS.
In many cases, the wall voltage is not sufficiently moved between the scan electrode and the sustain electrode due to the sustain discharge, and it becomes difficult to continuously generate the sustain discharge during the sustain period.

As described above, in the conventional driving method,
There has been a problem that the sustain discharge is not continuously performed in the sustain period and the discharge stability is deteriorated.

[0025]

In order to solve the above-mentioned problems, a method of driving a plasma display panel according to the present invention comprises a first substrate and a second substrate which are arranged opposite to each other with a discharge space interposed therebetween. A plurality of pairs of scan electrodes and sustain electrodes covered with a dielectric layer are arranged on one substrate, and a plurality of data electrodes orthogonal to the scan electrodes and the sustain electrodes are arranged on the second substrate. A method for driving a plasma display panel, comprising: an initialization period, a write period, a sustain period, and an erase period, wherein a high-level period of a sustain pulse waveform applied to a scan electrode and a sustain electrode is set to 2 uS or more during the sustain period. Is what is being done.

According to the present invention, continuous sustain discharge during the sustain period can be ensured, and the discharge stability can be improved.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. The panel used in the embodiment of the present invention is the same as the panel shown in FIG.
The electrode arrangement of this panel is the same as that shown in FIG. An operation timing chart showing a panel driving method according to an embodiment of the present invention is the same as that shown in FIG.
Therefore, their description is omitted.

(Embodiment 1) First, the first embodiment will be described below with reference to FIGS. 1, 2 and 3 with respect to differences from the conventional one.

[0029] Figure 1 of one subfield period, from the end of the writing period, represents the time of the sustain period and the erase period, a voltage waveform of all the scanning electrodes SCN ₁ ~SCN _n, all the sustain electrodes SUS _{1 to} SUS _n voltage waveforms,
And protective film 5 on scan electrode SCN _k and sustain electrode SUS _k (k is an integer of 1 to n) constituting predetermined discharge cell 12 in which write discharge occurred in the write period among all discharge cells 12. The surface wall voltage is shown.

[0030] maintained from the time of the writing period, for generating a first sustain discharge in a predetermined discharge cell, the voltage amplitude Vh' to all the scanning electrodes SCN ₁ ~SCN _n (V), the high level period of 2uS the pulse waveform is applied to hold all the sustain electrodes SUS ₁ ~SUS _n to 0V. Next, in order to generate the second sustain discharge, all the scan electrodes SCN ₁ to
SCN _n is maintained at 0 V, and all the sustain electrodes SUS _{1 to} SU
_An oscillating sustain pulse waveform is applied to Sn. Thus a sustain pulse is alternately applied to the scan electrodes and the sustain electrodes, the last sustain discharge is performed by applying the sustain pulse to all the scanning electrodes SCN ₁ ~SCN _n, 0V to all the sustain electrodes SUS ₁ ~SUS _n
Is generated by holding the Then, an erasing period in which an erasing waveform that gradually rises from 0 V to the potential Vr (V) is applied to all sustain electrodes SUS _{1 to} SUS _n is started.

The scanning electrodes SCN _k and sustain electrode SUS _k and accumulated wall voltage constituting a predetermined discharge cell 12 by the end the writing period, a high-level period of the sustain pulse 2
By setting to uS, a sufficient wall voltage moving time is obtained in each sustain discharge, so that the wall voltage does not decrease during the sustain period. For this reason, the sustain discharge during the sustain period can be continuously generated, and the discharge stability can be improved.

FIG. 2 shows that when the panel is caused to emit light by the driving method according to the first embodiment, the high-level period of the sustain pulse waveform is changed, and at this time, the sustain discharge is generated continuously and stably. FIG. 9 is a schematic diagram when a minimum voltage amplitude of a sustain pulse waveform that can be obtained is experimentally obtained. According to this, the high-level period of the sustain pulse waveform is 1.5 μS
By changing from Vh to 2.0 μS, the lowest voltage amplitude of the sustain pulse waveform has an effect of decreasing from Vh (V) to Vh ′ (V).

FIG. 3 shows the results obtained by measuring the discharge power and the light emission luminance of the panel when the voltage amplitude of the sustain pulse waveform is Vh and Vh '. By decreasing the voltage amplitude of the sustain pulse waveform from Vh to Vh ', the discharge power is reduced. The luminous efficiency (panel luminance / sustain discharge power) when the voltage amplitude is Vh is shown by the slope of the dotted line in FIG. 3, and similarly, the luminous efficiency when the voltage amplitude is Vh ′ is indicated by the dashed line in FIG. As indicated by the slope, it also has the effect of improving the luminous efficiency. For these reasons, it is possible to reduce the withstand voltage of the driving circuit and reduce the driving power.

In this embodiment, an example in which the high-level period of the sustain pulse is 2 μS has been described. However, in the method of driving the plasma display, the conditions for maintaining high image quality display by contrast, gradation, etc. Originally
The high-level period of the sustain pulse can be extended up to 5 μS.

(Embodiment 2) Next, a second embodiment will be described below with reference to FIG.

[0036] Figure 4, among the similarly one subfield period and 1, from the end of the writing period, represents the time of the sustain period and the erase period, all scan electrodes SCN ₁ ~
And the voltage waveform of the SCN _n, all the sustain electrodes SUS ₁ ~SUS
_n , and a scan electrode SCN _k and a sustain electrode SUS _k (k is 1 to 2) that constitute a predetermined discharge cell 12 in which a write discharge has occurred during a write period among all the discharge cells 12
The wall voltage on the surface of the protective film 5 on any integer of n) is shown.

In order to generate the first sustain discharge in a predetermined discharge cell from the end of the writing period, all scan electrodes SCN _{1 to} SCN _n maintain a voltage amplitude Vh ′ (V) and a high level period of 2 μS. the pulse waveform is applied to hold all the sustain electrodes SUS ₁ ~SUS _n to 0V. Next, in order to generate the second sustain discharge, all the scan electrodes SCN ₁ to
SCN _n is maintained at 0 V, and all the sustain electrodes SUS _{1 to} SU
_An oscillating sustain pulse waveform is applied to Sn. As described above, the sustain pulse is alternately applied to the scan electrode and the sustain electrode. In the last sustain discharge, the sustain pulse having the voltage amplitude Vh ′ high level period of 3.0 μS is applied to all the scan electrodes SCN _{1 to} SCN _n. Are generated by holding all the sustain electrodes SUS _{1 to} SUS _n at 0V. Then, all the sustain electrodes SU
An erase period in which an erase waveform that gradually rises from 0 V to the potential Vr ′ (V) is applied to S _{1 to} SUS _n is started.

At the end of the sustain period, all scan electrodes SCN ₁
ＳSCN _n to set the high-level period of the sustain pulse waveform to 3.0 μS, whereby the wall voltage in the last sustain discharge is sufficiently moved, and the scan electrode SCN
Many wall voltage is accumulated by the protective film 5 surface on _k and sustain electrodes SUS _k. As a result, the erase discharge in the subsequent erase period is likely to occur, lowering the Vr' (V) the voltage amplitude of the erase waveform applied to all the sustain electrodes SUS ₁ ~SUS _n from conventional Vr (V) It has the effect of doing. Moreover, since it is possible to cancel the wall voltage of the protective film 5 surface on the scanning electrode SCN _k and sustain electrodes SUS _k This erasing discharge, also acts to carry out an initialization operation in the initialization period of the next subfield normally Have. For these reasons, the withstand voltage of the drive circuit can be reduced, the power of the drive circuit can be reduced, and the discharge stability of the panel can be improved.

In the above embodiment, the scan electrode SC
The case has been described where the reference potential of each drive waveform applied to N _{1 to} SCN _n , sustain electrodes SUS _{1 to} SUS _n and data electrodes D _{1 to} D _m is 0 V, but the reference potential of each drive waveform is other than 0 V. The same applies when the potential is set.

Further, in this panel, since the periphery of the discharge cell is surrounded by a dielectric material and each drive waveform is applied to the discharge cell in a capacitively coupled manner, even if each drive waveform is level-shifted in a DC manner, the operation is performed. Is not to change.

[0041]

As described above, according to the driving method of the plasma display panel of the present invention, the high level period of the sustain pulse waveform applied to the scan electrode and the sustain electrode during the sustain period is set longer than before. By continuously and stably generating the sustain discharge in the sustain period, the discharge stability can be improved. Also, by reducing the voltage amplitude of the sustain pulse waveform and the voltage amplitude of the erase pulse waveform, the withstand voltage of the drive circuit can be reduced, and the cost of the drive circuit can be reduced.
Power consumption of the driver circuit can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a relationship between a scan electrode voltage and a sustain electrode voltage during a sustain period of a panel driving method according to a first embodiment of the present invention, and a wall voltage of each electrode surface.

FIG. 2 is a schematic diagram showing a high-level period of a sustain pulse waveform and a voltage amplitude of the sustain pulse waveform according to the embodiment;

FIG. 3 is a schematic diagram showing sustain discharge power and panel light emission luminance according to the embodiment.

FIG. 4 is a diagram showing a relationship between a scan electrode voltage and a sustain electrode voltage during a sustain period of a panel driving method according to a second embodiment of the present invention, and a wall voltage of each electrode surface.

FIG. 5 is a sectional perspective view showing a configuration of a plasma display panel.

FIG. 6 is a diagram showing an electrode arrangement of a plasma display panel.

FIG. 7 is an operation timing chart showing a driving method of a conventional plasma display panel.

FIG. 8 is a diagram showing a relationship between a scan electrode voltage and a sustain electrode voltage and a wall voltage on each electrode surface during a sustain period of the conventional panel driving method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 First glass substrate 2 Scan electrode 3 Sustain electrode 4 Dielectric layer 5 Protective film 6 Second glass substrate 7 Dielectric layer 8 Data electrode 9 Partition wall 10 Phosphor 11 Discharge space 12 Discharge cell

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Ryuji Kurata 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. (reference) 5C080 AA05 BB05 DD09 DD26 DD27 HH02 HH04 HH05 JJ04 JJ05 JJ06

Claims (3)

[Claims] A first substrate and a second substrate are disposed opposite each other with a discharge space interposed therebetween, and a plurality of pairs of scan electrodes and sustain electrodes covered with a dielectric layer are arranged on the first substrate. A method of driving a plasma display panel in which a plurality of data electrodes are arranged on the second substrate, the plurality of data electrodes being orthogonally opposed to the scan electrodes and the sustain electrodes.
A method for driving a plasma display panel, comprising a writing period, a sustaining period, and an erasing period, wherein a high-level period of a sustain pulse waveform applied to a scanning electrode and a sustaining electrode is set to 2 uS or more in the sustaining period. 2. The method of driving a plasma display panel according to claim 1, wherein the high level period of the sustain pulse waveform applied to the scan electrode and the sustain electrode during the sustain period is 2 μS or more and 5 μS or less. 3. A high level period of a sustain pulse waveform applied last to a scan electrode or a sustain electrode during a sustain period is as follows:
2. The driving method of a plasma display panel according to claim 1, wherein the duration is longer than a high level period of the other sustain pulse waveform in the sustain period, and the length is 3 μS or more.