JP2000293136A - Method for driving plasma display panel and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any unstable operation, and to suppress the generation of any branch-shaped protrusion by impressing a first maintaining pulse having polarity opposite to that of a scanning pulse, and width which is set for offsetting DC components due to a scanning base pulse according to the total of two sub-fields to scanning electrodes. SOLUTION: In a scanning period, an n-th sub-field(n-th SF) is scanned successively from a leading line(Ws1) to a tail line(Wsn), and a following (n+1)th sub-field((n+1)th SF) is scanned successively from the tail line to the leading line. Also, a first maintaining pulse Psf whose polarity is opposite to that of a scanning base pulse Pb is impressed to all scanning electrodes after the lapse of a prescribed time from the scanning pulse PW. Therefore, the first maintaining pulse Psf is impressed to the scanning electrodes so that any unstable operation due to the separation of a writing discharging period and a maintaining discharging period can be prevented, and that the generation of any branch-shaped protrusion due to a DC bias generated between the scanning electrodes and the maintaining electrodes can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for driving a plasma display panel, and more particularly to a method for driving an AC discharge type plasma display panel.

[0002]

2. Description of the Related Art In general, a plasma display panel (hereinafter, referred to as a PDP) has a thin structure, does not flicker, has a large display contrast ratio, can have a relatively large screen, and has a high response speed. It is fast, self-luminous and can emit multicolor by using phosphors.
It has many features. For this reason, in recent years, it has been widely used in the field of computer-related display devices and color image display.

[0003] Depending on the operation method, the PDP is operated in an AC discharge type in which the electrodes are covered with a dielectric and indirectly operated in an AC discharge state, or in an DC discharge state in which the electrodes are exposed to a discharge space. Although there is a direct current discharge type, the alternating current discharge type has a feature that the electrode can be prevented from being sputtered by electric discharge and has a long life.

Further, the AC discharge type includes a memory operation type using a memory function of a display cell and a refresh operation type using no memory effect as driving methods.

The brightness of a PDP is proportional to the number of discharges, that is, the number of repetitions of an applied pulse within a predetermined time (for example, one frame). In the refresh operation type, as the display capacity increases, the brightness decreases. PD of
Used only in P. Therefore, at present, an AC discharge memory type PDP is mainly used because of its advantages such as long life and high luminance.

FIG. 13 is a perspective sectional view of a display cell showing an example of the configuration of an AC discharge memory type plasma display panel.

As shown in FIG. 13, a display cell of an AC discharge memory type PDP includes a first insulating substrate 101 and a second insulating substrate 102 made of glass provided on the back and front surfaces of the panel, respectively. A transparent scan electrode 103 and a sustain electrode 104 formed at predetermined intervals on the second insulating substrate 102; and a scan electrode 103 and a sustain electrode 104
A first trace electrode 105 and a second trace electrode 106, which are stacked on the scan electrode 103 and the sustain electrode 04, respectively, in order to reduce the electrode resistance value of
A first dielectric 112 formed so as to cover the scan electrode 103, the sustain electrode 104, the first trace electrode 105, and the second trace electrode 106, respectively; A protection layer 113 made of magnesium oxide or the like for protecting the first dielectric 112 from discharge; a data electrode 107 disposed on the first insulating substrate 101 and formed in a direction orthogonal to the scan electrode 103 and the sustain electrode 104; A second dielectric 114 formed so as to cover the data electrode 107, and a rare gas such as helium, neon, xenon, or the like, formed between the first insulating substrate 101 and the second insulating substrate 102. A discharge gas space 108 filled with a discharge gas composed of a mixed gas, and a discharge gas space 108 provided on the second dielectric 114 to form It is composed of a partition wall 109 for cutting, and a phosphor 111 that is applied on the second dielectric 114 and on the side surface of the partition wall 109 and converts ultraviolet light generated by discharge generated in the discharge gas space 108 into visible light 110. I have.

In an actual PDP, for example, a VGA color display panel, 480 display cells in the vertical direction and 1920 display cells in the horizontal direction are arranged in a grid pattern, and the scan electrode 103 and the sustain electrode 104 are respectively arranged. 480 data electrodes 107 and 1920 data electrodes 107 are provided.

Next, the discharging operation of the PDP configured as described above will be described.

[0010] In the display cell shown in FIG.
When a pulse voltage exceeding the discharge threshold voltage is applied between the gate electrode 03 and the data electrode 107, discharge is started, and positive and negative charges (wall charges) corresponding to the polarity of the pulse voltage are applied to the first dielectric material. It is sucked and deposited on the surfaces of 112 and the second dielectric 114, respectively. The equivalent internal voltage generated due to the accumulation of the charges, that is, the wall voltage has a polarity opposite to that of the applied pulse voltage, so that the effective voltage inside the cell decreases as the discharge grows, and the pulse voltage is reduced. Even if it is kept at a constant value, the discharge cannot be maintained, and eventually the discharge stops.

Thereafter, scan electrode 103 and sustain electrode 104
When a sustain pulse, which is a pulse voltage having the same polarity as the wall voltage, is applied between the wall voltage and the wall voltage, the wall voltage is superimposed as an effective voltage,
Thus, even if the voltage amplitude of the sustain pulse applied from the outside is small, the discharge can be caused to exceed the discharge threshold. Therefore, the discharge is maintained by continuously applying the sustain pulse between scan electrode 103 and sustain electrode 104.

The scanning electrode 103 or the sustain electrode 10
The sustain discharge described above can be stopped by applying a sustaining erase pulse, which is a pulse having a width of about a low voltage or a width of about a sustaining pulse having a narrow width to neutralize the wall voltage.

FIG. 14 is a plan view showing a schematic configuration of a plasma display panel formed by arranging the display cells shown in FIG. 13 in a matrix.

As shown in FIG. 14, a PDP is a display panel capable of displaying a dot matrix in which display cells 120 are arranged in m × n rows and columns. Scanning electrodes arranged in parallel with each other are used as row electrodes. The electrodes Sc ₁ , Sc ₂ ,
..., Sc _m, and sustain electrodes Su _1, Su _2, ..., includes a Su _m, as the column electrodes, data electrodes D ₁ arranged so as to be perpendicular to these scanning electrodes and sustain electrodes, D _2, ..., D _n .

[0015] When the light emission of the display cell 120, the scan electrodes Sc _1, Sc _2, ..., while sequentially applying a scan pulse to Sc _m, data electrode Di of the display cells to be displayed in synchronization with the scanning pulse A data pulse is selectively applied to (1 ≦ i ≦ n), and a voltage exceeding a discharge threshold is applied to a desired display cell 120 to emit light. Further, after the scan electrodes _{Sc 1, Sc 2, ...,} Sc m and sustain electrodes S
u _1, Su _2, ..., to sustain the light emission by applying a sustain pulse for sustaining a discharge between Su _m.

Next, a method of driving a conventional plasma display panel will be described with reference to the drawings.

The driving method of the AC discharge memory type PDP includes:
A scan sustain separation drive type in which display data for one frame (or one subfield to be described later) is sequentially written for each scan line, and then a sustain pulse is simultaneously applied to each display cell; There is a scan sustained mixed drive type in which display data is sequentially written for each scan line while constantly applying a sustain pulse to a cell. Hereinafter, a conventional PDP driving method will be described by taking a scanning sustaining separation driving type as an example.

FIG. 15 is a diagram showing a conventional method for driving a plasma display panel, and is a waveform diagram showing a state of a pulse waveform applied to each electrode.

In FIG. 15, Wu is a sustain electrode Su ₁ ,
Su _2, ..., a sustain electrode driving voltage waveform to be applied in common to _{Su m, Ws 1, Ws 2} , ..., Ws m scan electrodes Sc _1,
Sc2, ..., a scan electrode driving voltage waveform applied to Sc _m. Further, Wd data electrodes D _1, D _2, ..., a data electrode driving voltage waveform applied to D _n, Ws ₁ -Wu is a waveform showing a potential difference between the scan electrodes Sc ₁ and the sustain electrode. Incidentally, shows only a potential difference between the sustain electrodes and the scan electrodes Sc ₁ in FIG. 15, the generation timing of the potential difference due to the scanning pulse Pw is similar potential except different occurs in other scanning electrodes.

As shown in FIG. 15, one cycle of the driving sequence is composed of a preliminary discharge period A, a write discharge period B, and a sustain discharge period C. These discharge periods are repeatedly executed, so that the PDP can operate in a desired manner. Can be displayed.

The preliminary discharge period A is a period for generating active particles and wall charges in a discharge gas space (see FIG. 13) in order to obtain a stable write discharge characteristic in the write discharge period B. After applying a pre-discharge pulse Pp for simultaneously discharging the display cells to the sustain electrode, a pre-discharge erase pulse Ppe for extinguishing, among the wall charges generated during the pre-discharge period A, a charge that hinders the writing discharge and the sustain discharge. Is simultaneously applied to each scanning electrode.

That is, first, the sustain electrodes Su ₁ , Su
2, ..., by applying a preliminary discharge pulse Pp respect Su _m,
After causing discharge in all the display cells, the scan electrodes Sc _1, Sc _2, ..., preliminary discharge erase pulse Ppe to Sc _m
Is applied to generate an erase discharge, and among the wall charges deposited by the preliminary discharge pulse Pp, charges that inhibit the write discharge and the sustain discharge are erased.

[0023] In the writing discharge period B, the first, all the scanning electrodes Sc _1, Sc _2, ..., and applies a scan base pulse Pb to Sc _m, further scan electrodes Sc _1, Sc _2, ...,
It applied with a scan pulse Pw in order to sc _m, in synchronism with the scanning pulse Pw, and selectively applying a data pulse Pd to the data electrode Di of the display cells to be displayed, generating a write discharge in a cell to be displayed To generate wall charges.

The value of the scan pulse Pw can be reduced by applying the scan base pulse Pb.
As a result, the maximum operating voltage of the high withstand voltage driving IC for generating the scanning pulse Pw can be reduced, and the cost of the IC can be reduced. When the value of the scan pulse Pw is large, erroneous discharge is likely to occur at the time of level transition at the end of the scan pulse Pw. Such a discharge eliminates the write discharge generated by the scan pulse and the data pulse. It is a harmful discharge. Therefore, the value of the scan pulse Pw is reduced by applying the scan base pulse Pb,
Prevent this harmful discharge.

In the sustain discharge period C, the sustain electrodes Su
_1, Su _2, ..., to apply a respective sustain pulses Pu in Su _m, than the sustain pulse Pu to the scanning electrodes 18
A sustain pulse Ps delayed by 0 degrees is applied, thereby maintaining a discharge necessary for obtaining a desired luminance for a display cell in which display data is written in the writing discharge period B. Finally, a sustain erase pulse Pe is applied to each of the scan electrodes Sc ₁ , Sc ₂ ,..., Sc _m to stop the sustain discharge.

Hereinafter, a driving method for performing multi-gradation display with the above-described PDP will be described.

In a PDP, unlike a CRT, it is difficult to perform multi-gradation display by changing an applied voltage. Therefore, multi-gradation display is generally performed by controlling the number of times of light emission. In particular, in order to perform multi-brightness display with high brightness,
The subfield method described below is used.

FIG. 16 is a diagram showing a conventional method of driving a plasma display panel, and is a time chart for explaining a subfield method for performing multi-tone display. FIG. 16 shows an example in the case of displaying 2 ⁶ = 64 gradations. Further, FIG. 16 shows a case where the preliminary discharge is performed only once at the end of one frame, but the preliminary discharge may be performed at the beginning of each subfield similarly to the drive sequence shown in FIG.

Normally, the time of one frame varies depending on the individual computer or broadcasting system, but is generally about 1/4.
It is often set in the range of 7 seconds to 1/76 seconds. In the multi-tone display by the PDP, as shown in FIG. 16, one frame has k subfields (S in FIG. 16).
F1 to SF6 (k = 6 subfields), and each subfield is driven according to the driving sequence shown in FIG.

Each of the subfields is given a temporal weight with respect to each of the sustain light emission times, and the light emission luminance of each pixel is controlled as follows.

[0031]

(Equation 1) Here, n is the number of the subfield, and the subfield with the lowest luminance is 1 and the subfield with the highest luminance is k. Further, L ₁ is a luminance of the lowest luminance subfields. It is a _n is a variable which takes the value of 1 or 0, if the n th subfield emit the pixels 1, if not to emit light is zero.

As described above, in the subfield method, the luminance can be controlled by selecting the lighting / non-lighting of each subfield. The time length of each sub-field shown in FIG. 16 is set according to the number of sustain discharges in each sub-field, that is, the difference in the number of sustain pulses Pu and Ps.

In a PDP, electrodes are formed on an insulating substrate made of glass, and the electrodes are covered with a glass glaze, which is a dielectric made of glass paste. Therefore, if there is a predetermined or more potential difference between the average voltage applied between the scan electrode and the sustain electrode,
Due to the DC bias electric field, an ion component in the glass grace moves, and a degradation phenomenon called electromigration occurs, in which the ion component precipitates on the surface of the electrode and grows a conductive dendritic projection.

For example, in the case of the conventional PDP driving method shown in FIG. 15, the potential difference between the scan electrode Sc ₁ and the sustain electrode Su ₁ changes as shown by Ws ₁ -Wu. As shown in FIG. 15, in the sustain discharge period C, positive and negative pulse potential differences are generated alternately, so that each pulse is canceled and no DC bias component is generated. In general, the preliminary discharge period A is sufficiently shorter than the write discharge period B and the sustain discharge period C, so that the influence of the potential difference applied during that period can be reduced. Therefore, it is considered that the DC bias component between the scan electrode and the sustain electrode is mainly generated by the scan base pulse Pb applied to the scan electrode during the write discharge period B.

FIG. 17 is a schematic diagram showing the growth mechanism of dendritic projections caused by a DC bias. FIG. 17 shows only the structure of the scanning electrode and the sustain electrode, the insulating substrate (the second insulating substrate shown in FIG. 13) sandwiching them, and the dielectric, and the dielectric material is lead glass (PbO 2). ) And soda-lime glass (Na ₂ O.Ca)
This shows a case where a Na-containing glass typified by O.SiO) is used.

In FIG. 17A, when a DC voltage is applied between the scan electrode and the sustain electrode, the N
a is ionized and moves to the negative electrode side (the scanning electrode in FIG. 17A). At this time, the Na ions receive electrons (2e ⁻ ) from the negative electrode and become Na atoms.

In the above process, the concentration of Na increases on the surface of the negative electrode in contact with the insulating substrate. However, since Na has a large ionization tendency, it is ionized again near the negative electrode. At this time, Pb is reduced by reacting with PbO in the dielectric near the plane of the insulating substrate instead of giving electrons to the electrodes to reduce them (since the electrodes are negatively biased) (FIG. 17B). ). Pb atoms generated by such a chemical reaction become main components of the conductive dendritic projection. Dendrites grow in the direction of the positive electrode from near the negative electrode,
Eventually, a short circuit occurs between the scan electrode and the sustain electrode.
Even if a short circuit does not occur, since the dendritic projection is a conductive substance, the effective electrode area is increased, and the discharge gap between the scanning electrode and the sustain electrode is reduced. As a result, the discharge start voltage drops significantly in a short time, and even if the voltage is set so that a normal image is displayed on the initial screen, erroneous lighting occurs after a short display operation, and the normal operation is maintained. It may not be possible.

In order to prevent the occurrence of such electromigration, for example, Japanese Patent Application Laid-Open No.
Japanese Patent Application Publication No. 0909 discloses an example of the countermeasure.

FIG. 18 is a waveform chart showing an example of a conventional driving method of a plasma display panel for preventing electromigration. Incidentally, FIG.
-160909.

In FIG. 18, A is a preliminary discharge period, B is a write discharge period, C is a sustain discharge period, Pp is a preliminary discharge pulse, Pb is a scan base pulse, Pw is a scan pulse,
Px is a pulse having a voltage of 50 V, Pu is a sustain pulse on the sustain electrode side, and Ps is a sustain pulse on the scan electrode side.

In the present embodiment, of the sustain pulses applied to the scan electrodes, the last sustain pulse applied in the sustain discharge period C is continuously extended and applied to the pause period provided after the sustain discharge period C. The compensation pulse cancels out the DC bias component applied between the scan electrode and the sustain electrode during the write discharge period B.

[0042]

Problems to be Solved by the Invention
In the conventional method of driving a plasma display panel described in Japanese Patent Application Laid-Open No. 9-209, a DC bias component applied between a scan electrode and a sustain electrode during a write discharge period is canceled by applying a compensation pulse during a pause period. And the write discharge period need to be set to the same length. However, the pause period and the write discharge period cannot always be set to the same length. Conversely, if the pause period is set to the same length as the write discharge period, the length of the sustain discharge period is reduced. As a result, there is a possibility that sufficient luminance cannot be obtained.

The voltage of the sustain pulse applied at the end of the sustain discharge period is different from the voltage of the scan base pulse Pb applied between the scan electrode and the sustain electrode during the write discharge period. Since the voltage changes non-linearly with respect to the voltage of the sustain pulse applied at the end of the sustain discharge period, the voltage and the pulse width of the compensation pulse necessary to completely cancel the DC bias component applied during the write discharge period are reduced. There is a problem that it is difficult to determine.

In order to solve such a problem, the applicant has disclosed in Japanese Patent Application No. 9-256624 a PDP in which a compensation pulse is inserted between a preliminary discharge period and a write discharge period or between a write discharge period and a sustain discharge period. Is proposed.

In Japanese Patent Application No. 9-256624, a display area of a PDP is divided into two parts. When one display area is in a writing discharge period, a compensation pulse is applied to the other display area, and a compensation pulse is applied to one display area. Is applied, the other display area is set as a writing discharge period.

Incidentally, the easiness of occurrence of discharge in a display cell generally depends on the number of active particles (charged particles or excited particles) in the discharge space, and the greater the number of active particles, the easier the discharge is generated. Therefore, if the time from the occurrence of discharge to the next application of a pulse for discharge is long, the number of active particles in the discharge space decreases, and as shown in FIG. (The time difference until the occurrence of) becomes longer. If the discharge delay time exceeds the width of the applied pulse, no discharge occurs. Therefore, the closer the interval between the applied pulses, the worse the discharge characteristics.

PD described in Japanese Patent Application No. 9-256624
In the driving method of P, scanning is performed sequentially from the first row of the scanning line, and thereafter, the sustain discharge is started at the same timing in all the cells. Therefore, the time from the write discharge to the sustain discharge is longer as being closer to the first row, The closer to the last line, the shorter. For this reason, the discharge characteristics at the time of applying the first sustain pulse in the sustain period are different in the panel surface, which causes the margin of the drive voltage to be narrowed.

The present invention has been made to solve the above-mentioned problems of the prior art, and prevents an unstable operation due to a separation between a write discharge period and a sustain discharge period. It is an object of the present invention to provide a driving method and a driving apparatus for a plasma display panel, which suppress the generation of dendritic protrusions due to a DC bias between electrodes and sustain electrodes.

[0049]

In order to achieve the above object, a method of driving a plasma display panel according to the present invention is directed to a plasma display panel of an AC discharge memory type comprising a plurality of display cells arranged in a grid. A method of driving a scan-maintenance separation type plasma display panel for displaying a desired image while displaying a multi-gradation using a method, wherein each scan electrode is provided within a scan period in the scan-maintenance separation type drive sequence. The scan pulse is superimposed on the scan pulse and applied in a predetermined order, and the data pulse is applied to a predetermined data electrode to selectively write the video data. After a time, the scan base pulse has the opposite polarity to the scan pulse and is the sum of two subfields. The first sustain pulse with the width to offset the DC component is applied to the scanning electrode is a method of performing initial sustain discharge between the sustain electrode.

Here, one of the two sub-fields sequentially writes video data to each scanning line from one end of the plasma display panel to the other end thereof, and On the other hand, video data may be sequentially written to each scanning line from the other end to the one end of the plasma display panel, and one of the two subfields may be written from one end of the plasma display panel to the other. Image data is sequentially written to each scan line toward the end, and in the other of the two sub-fields, the entire scan electrode is divided into two in the scan line direction, and the intermediate scan of the plasma display panel is performed. After writing video data in order from the line to the other end, the plasma Toward the one end side of the play panel to the middle of the scan line may sequentially write the video data.

Further, the whole scanning electrode is divided into a plurality of sub-scanning electrode groups in the scanning line direction, and one of the two sub-fields is connected to one end of the plasma display panel for each of the sub-scanning electrode groups. It is also possible to write video data sequentially to each scanning line from the side to the other end, and to write video data sequentially from the other end to the one end of the plasma display panel in the other of the two subfields. Preferably, the entire sustain electrode is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and the first sustain pulse is applied to each of the sub-scan electrode groups and the sub-sustain electrode groups. Immediately after that, the sustain discharge may be started.

Further, the width of the scan base pulse and the width of the first sustain pulse may be equal for each scan electrode in the total of the two subfields, and the scan applied to all scan electrodes may be equal. The widths of the base pulses may be equal.

On the other hand, the driving apparatus for a plasma display panel according to the present invention performs multi-gradation display on a plasma display panel of an AC discharge memory type comprising a plurality of display cells arranged in a lattice by using a subfield method. What is claimed is: 1. A scan maintaining / separating type plasma display panel driving apparatus for displaying a desired image, wherein a scanning pulse is superimposed on a scanning base pulse on each scanning electrode within a scanning period in the scan maintaining / separating type driving sequence. And in the order of, and selectively write video data by applying a data pulse to a predetermined data electrode, and after applying the scan pulse for approximately a fixed time, with a polarity opposite to the scan pulse, and A first set to a width that cancels out the DC component due to the scan base pulse in the sum of the two subfields The sustain pulse is applied to the scanning electrode is configured to have a scan electrode driver for making the first sustain discharge between the sustain electrode.

Here, the scanning electrode driver includes the 2
In one of the two sub-fields, the scan pulse is sequentially applied to each of the scan electrodes from one end to the other end of the plasma display panel, and in the other of the two sub-fields, the plasma display The scan pulse may be sequentially applied to each scan electrode from the other end of the panel toward one end, and one of the two subfields may be applied from one end to the other end of the plasma display panel. The scan pulse is applied to each scan electrode in turn, and in the other of the two subfields, the entire scan electrode is divided into two in the scan line direction, and the middle scan electrode of the plasma display panel From the one end of the plasma display panel after applying the scanning pulse in order from Towards the serial middle scan electrode may be applied to the scan pulse sequentially.

Further, the scan electrode element driver divides the entire scan electrode into a plurality of sub-scan electrode groups in the scan line direction, and for each of the sub-scan electrode groups, one of the two sub-fields is used. The scan pulse is sequentially applied to each scan line from one end of the plasma display panel toward the other end, and the other of the two subfields is applied from the other end to the one end of the plasma display panel. The scan pulse may be sequentially applied toward the sub-scan electrode group, and the entire sustain electrode is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and the first sustain A sustain electrode driver for applying a sustain pulse for performing a sustain discharge to the sustain electrode immediately after the application of the pulse; The sustain discharge pulses for performing sustain discharge immediately after applying the first sustain pulses per group may be applied.

Further, the scan electrode driver may equalize the width of the scan base pulse and the first sustain pulse for each scan electrode in the total of the two subfields. A scanning base pulse of equal width may be applied to the electrodes.

According to the above-described method of driving the plasma display panel, a scan pulse is applied to each scan electrode in a predetermined order while being superimposed on a scan base pulse during a scan period in a scan sustaining-separation type drive sequence.
The video data is selectively written by applying a data pulse to a predetermined data electrode.
By applying a first sustain pulse set to a width that cancels out the DC component due to the scan base pulse in the total of two subfields to the scan electrode, unstable operation due to separation between the write discharge and the sustain discharge period is prevented. Thus, the generation of dendrites due to the DC bias generated between the scan electrode and the sustain electrode is suppressed.

Further, the entire scanning electrode is divided into a plurality of sub-scanning electrode groups in the scanning line direction,
In one of the two subfields, video data is sequentially written to each scanning line from one end of the plasma display panel to the other end, and the other of the two subfields is the other end of the plasma display panel. By writing video data in order from one end to the other end, a circuit for applying a sustain pulse to the scan electrodes can be shared for each sub-scan electrode group.

Further, the entire sustain electrode is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and each of the sub-scan electrode groups and the sub-sustain electrode groups is immediately after the first sustain pulse is applied. By starting the sustain discharge, the sustain discharge can be performed more stably.

Further, by outputting the scan base pulses applied to all the scan electrodes with the same width, the scan base pulses can be shortened.

[0061]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing the configuration of a first embodiment of a driving apparatus for a plasma display panel according to the present invention.

In FIG. 1, the PDP driving apparatus according to the present embodiment includes a data electrode driver 2 for applying a voltage corresponding to a video signal to each data electrode 7 of the PDP 1, and a PDP 1
Sustain electrode driver 6 for applying a predetermined pulse voltage to each of sustain electrodes 4 and scan electrode driver 5 for applying a predetermined pulse voltage to each of scan electrodes 3 of PDP 1
And a vertical synchronizing signal, a horizontal synchronizing signal,
An interface circuit 8 for outputting a control signal to each driver based on the video data, a data power supply 9 for supplying a voltage (+ Vd) for outputting a data pulse from the data electrode driver 2, a sustain electrode driver 6, A sustain power supply 10 for supplying a voltage (+ Vs) for outputting a sustain pulse from scan electrode driver 5, and a voltage (-Vw) for outputting a scan pulse and scan base pulse for outputting scan pulse from scan electrode driver 5. And a reset power supply 1 for supplying a voltage (+ Vp) for causing the scan electrode driver 5 to output a preliminary discharge pulse.
2 and an erasing power supply 1 for supplying a voltage (−Vpe) for outputting a preliminary discharge erasing pulse from the scan electrode driver 5.
3.

The vertical synchronizing signal supplied from the outside to the interface circuit 8 is a signal for defining the cycle of one frame, and the horizontal synchronizing signal synchronizes in the horizontal direction similarly to the horizontal synchronizing signal which is a control signal of the CRT. It is a signal to take. The video data is a signal that specifies each display cell to emit or not emit light according to the video signal.

The interface circuit 8 includes, for example, a frame memory for temporarily storing video data, a memory control unit for reading video data from the frame memory and transferring it to the data electrode driver 2 in accordance with the PDP write timing, and a PDP drive sequence. And a signal processing unit that synchronizes the operation timing of each driver by matching the operations of the memory control unit and the driver control unit.

FIG. 2 shows the data electrode driver shown in FIG.
FIG. 3 is a block diagram illustrating a configuration example of a sustain electrode driver and a scan electrode driver.

In FIG. 2, the data electrode driver 2 is
Multiple data drivers 2 for outputting data pulses
Reference numeral 1 denotes a configuration connected to each data electrode. The data driver 21 is composed of a push-pull connected P-channel FET and an N-channel FET. The source of the P-channel FET of each data driver 21 is supplied with + Vd from the data power supply 9, and the source of the N-channel FET is ground potential. It is connected to the.

The sustain electrode driver 6 has a configuration in which a sustain driver 61 for outputting a sustain pulse is connected to all the sustain electrodes 4 in common. The sustain driver 61 includes a push-pull connected P-channel FET and an N-channel FE.
T, the P channel F of the sustain driver 61
+ Vs is supplied from the maintenance power source 10 to the source of ET,
The source of the N-channel FET is connected to the ground potential.

Scan electrode driver 5 includes a plurality of scan drivers 51 for respectively outputting scan pulse Pw and scan base pulse Pb, a plurality of sustain drivers 52 for respectively outputting sustain pulse Ps, and a preliminary discharge pulse Pp. And a reset driver 53 for outputting the preliminary discharge erasing pulse Ppe.

The scan driver 51 is composed of two P-channel FETs that supply -Vw and -Vb supplied from the scan power supply 11 to the scan electrode 3 at a predetermined timing. It is composed of a P-channel FET that supplies the supplied + Vs to the scanning electrode 5 at a predetermined timing, and a P-channel FET that connects the scanning electrode 5 to the ground potential at a predetermined timing. The reset driver 53 includes two drive circuits including a P-channel FET and an N-channel FET connected in a push-pull manner. One of the drive circuits receives + Vp and −Vpe supplied from the reset power supply 12 and the erase power supply 13. It is simultaneously supplied to each scanning electrode 3 at a predetermined timing, and the other drive circuit supplies each scanning electrode 3
Are simultaneously connected to the ground potential at a predetermined timing.

Next, a method of driving the plasma display panel of the present embodiment will be described with reference to the drawings.

FIG. 3 is a diagram showing a first embodiment of the driving method of the plasma display panel according to the present invention, and is a timing chart showing a state of a pulse waveform applied to each electrode.

In FIG. 3, Wu is a sustain electrode drive voltage waveform applied to each sustain electrode 4 in common, and Ws ₁ , Ws
s ₂ ,..., Ws _m are scan electrode drive voltage waveforms applied to each scan electrode 3. Wd is a data electrode drive voltage waveform applied to each data electrode 7.

The driving method of the PDP of the present embodiment is a scan sustaining separation driving type. One cycle of the driving sequence includes a reset period for applying a preliminary discharge pulse Pp and a preliminary discharge erase Ppe, and a reset period for applying video data. The scan pulse Pw is applied to the scan electrode (applied superimposed on the scan base pulse Pb), the scan period in which the data pulse Pd is applied to the data electrode to be displayed, and the sustain pulse Ps for performing the sustain discharge. , And a discharge period is repeatedly executed to display a desired image on the PDP.

Further, in order to perform multi-gradation display, one cycle (one frame) for displaying one screen is divided into a plurality of subfields (SF). In FIG. 3, two consecutive
3 illustrates two subfields. Also, as shown in FIG. 15, in the conventional driving sequence, the sustain discharge is stopped by applying the sustain erasing pulse at the end of the sustain period. However, in the driving method of the present embodiment shown in FIG. No sustain erasing pulse was applied. In the case of the driving method shown in FIG. 3, the operation of applying the preliminary discharge pulse Pp and the preliminary erase pulse Ppe during the reset period of the next subfield also serves as the operation of stopping the sustain discharge.

As shown in FIG. 3, in the PDP driving method of the present embodiment, during the scanning period, in the n-th sub-field (n-th SF), from the top line (Ws ₁ ) to the last line (Ws _m ) in order. In the subsequent (n + 1) th subfield ((n + 1) SF), scanning is performed in order from the last line to the first line. Further, a first sustain pulse Psf having a polarity opposite to that of the scan base pulse Pb is applied to all the scan electrodes after a lapse of a predetermined time from the scan pulse Pw. At this time, the first sustain pulse Psf is preferably applied within as short a time as possible within several tens of μs after the application of the scanning pulse Pw, and more preferably within 10 μs.

Further, the width of the first sustain pulse Psf applied to each scanning electrode is made longer as it is closer to the head line in the n-th subfield, and is shorter as it is closer to the head line in the (n + 1) -th subfield. Set as follows. It should be noted that the width of the first sustain pulse Psf does not necessarily need to be different for each scanning line, and tends to be longer in the n-th subfield nearer to the head line and shorter in the (n + 1) th subfield nearer to the head line. , There may be scan lines set to the same width.

Further, the sum (Lb _nSF + Lb _{(n + 1) SF} ) of the widths of the scanning base pulses Pb of the n-th subfield and the _{(n + 1) -th} subfield applied to each scanning electrode is made equal. The sum ( _LsnSF + Ls _{(n + 1) SF} ) of the widths of the first sustain pulse Psf in the nth subfield and the _{(n + 1) th} subfield applied to each scan electrode is set to be equal.

At this time, the width of the first sustain pulse Psf is defined as the sum of the widths of the nth subfield and the _{(n + 1) th subfield} ( _LsnSF + Ls _{(n + 1) SF} ). The sum of the widths of the scanning base pulse Pb in the (n + 1) th subfield (Lb _nSF + L
b _{(n + 1) SF} ) is set to a value that offsets the DC bias component.

For example, the width of the first sustain pulse Psf is calculated as follows.

FIG. 4 is a graph showing the capacitance between a scan electrode and a sustain electrode (one set) after a DC voltage is applied between the scan electrode and the sustain electrode for a predetermined time.

As shown in FIG. 4, when a DC voltage of 60 V is applied between the scanning electrode and the sustain electrode, the capacitance hardly changes, and when the DC voltage is higher than 60 V, the electrostatic capacity changes with time. The capacity increases. This is because the application of the DC voltage generates dendrites and changes the discharge gap between the surface electrodes. When the DC voltage is 60
Up to V, dendrites hardly grow, and the change with time in the capacitance is not proportional to the voltage value.

In consideration of the above, generation of dendritic projections is performed by applying an electric field in the opposite direction to a voltage bias (DC bias component) obtained as a result of integrating the voltage over one cycle of the driving sequence. In order to suppress this, the compensation pulse needs a width obtained by the following equation (2).

A = B × {(DE) / (CE)} ^F (2) As described above, assuming that the bias of the DC voltage is generated by applying the scanning base pulse, A becomes Compensation pulse width, B is scanning base pulse width, C is compensation pulse voltage, D
Is a scanning base voltage, E is a threshold voltage at which dendrites grow, and F is a correction coefficient. E and F are different values depending on the material.

Therefore, the first of the n-th subfield
Width Ls _nSF sustain pulse Psf, and first width Ls of the sustain pulse Psf _{(n + 1) SF} (n + 1) -th subfield
Is given by Ls _nSF + Ls _{(n + 1) SF} from the value A obtained by equation (2).
= 2A.

By applying such a first sustain pulse Psf to each scan electrode, it is possible to prevent an unstable operation due to a separation between the write discharge period and the sustain discharge period, and to prevent the scan electrode from sustaining. Generation of dendritic protrusions due to a DC bias component between the electrodes can be suppressed.

Further, even if the width of the first sustain pulse Psf of the last line of the n-th subfield is reduced, the first sustain pulse Psf applied in the set of subfields (the (n + 1) th subfield) is set. Thus, the DC bias component due to the scanning base pulse Pb can be canceled. Similarly, even if the width of the first sustain pulse Psf in the first line of the (n + 1) th subfield is reduced, scanning is performed by the first sustain pulse Psf applied in the set of subfields (nth subfield). The DC bias due to the base pulse Pb can be canceled. Therefore, even if the width of the first sustain pulse is set to a width that functions sufficiently as a compensation pulse, there is no temporal compression such as a limited sustain time. In the present embodiment, the method of canceling the DC bias component by combining two consecutive subfields has been described, but the subfields to be combined need not be continuous.

FIG. 5 is a view showing the state of the wall charges generated by the driving method shown in FIG. 3, and is a schematic view showing the state before and after the application of the scanning pulse and the first sustain pulse.

First, the state of the wall charges before and after the application of the scanning pulse will be described with reference to FIG.

When the scanning pulse Pw and the data pulse Pd are simultaneously applied to the selected display cell during the scanning period, a counter discharge occurs in the discharge gas space between the scanning electrode and the data electrode. At this time, the discharge resistance is reduced by the active particles generated in the discharge gas space, and a surface discharge occurs between the scan electrode and the sustain electrode. Therefore, positive charges are generated on the scan electrodes, and negative charges are generated on the sustain electrodes and the data electrodes.

Subsequently, a first sustain pulse Ps is applied to the scan electrode.
When f is applied, since the sustain electrode and the data electrode have negative charges, as shown in FIG. 5B, surface discharge occurs between the scan electrode and the sustain electrode, and between the scan electrode and the data electrode. Opposing discharge occurs. There is a protective layer typified by MgO on the sustain electrode, and since the protective layer has a large electron emission coefficient γ, secondary electrons are likely to be emitted by atomic collision. Since the secondary electrons are accelerated by the electric field and ionize the atoms to grow the discharge, a surface discharge occurs stronger than the counter discharge here, and a large amount of wall charges are formed between the scan electrode and the sustain electrode.

In this embodiment, since the time from the application of the scanning pulse Pw to the application of the first sustain pulse Psf is sufficiently short, the discharge by the first sustain pulse Psf is easily generated, and the first sustain pulse Psf is easily generated. As described above, the wall charges increase due to the surface discharge by the sustain pulse Psf. Therefore, even if there is a pause between the application of the first sustain pulse Psf and the next application of the sustain pulse Ps, the sustain pulse Ps
Susceptibility is likely to occur.

Further, since the time from the write discharge to the sustain discharge becomes equal for all the scan electrodes, the discharge characteristics by the first sustain pulse Psf can be made uniform.

(Second Embodiment) FIG. 6 is a diagram showing a second embodiment of the method of driving a plasma display panel according to the present invention, and is a timing chart showing a state of a pulse waveform applied to each electrode. is there. Note that Ws ₁ -Wu is a waveform indicating a potential difference between the scan electrode Sc ₁ and the sustain electrode Su ₁ .

As shown in FIG. 6, in the PDP driving method according to the present embodiment, during the scanning period, in the n-th sub-field (n-th SF), scanning is performed in order from the first line to the last line, and the subsequent (n + 1) -th sub-field is scanned. Field ((n +
1) SF), first, the central scanning line (W
(sm _{/ 2} ) to the last line, and then sequentially from the top line to the center scanning line (Wsm _{/ 2-1} ). Further, a scanning base pulse Pb having the same width is applied to all the scanning electrodes.

Further, in the first half (Ws _{1 to} Ws _{m / 2-1} ) of the scanning period in the n-th sub-field, a wide first sustain pulse Psf is applied, and the second half of the scanning period in the n-th sub-field is applied. applying a first sustain pulse Psf of (Ws _m / 2 ~Ws _m) in equal sustain pulse Ps width.
Further, by applying a first sustain pulse Psf equal width half (Ws _m / ₂ ~Ws m) the sustain pulse Ps of the scanning period in the subfield of the (n + 1), in the latter half of the scanning period in the subfield of the (n + 1) is (Ws ₁ ~W
s _{m / 2-1} ) Apply a wide first sustain pulse Psf. At this time, the width of the wide first sustain pulse Psf is set to a width that cancels the DC bias component of each scanning line in the nth subfield and the (n + 1) th subfield. The other driving method and the configuration of the driving device are the same as those of the first embodiment, and thus the description thereof is omitted.

As in the present embodiment, the same effect as in the first embodiment can also be obtained by a driving method in which the scanning direction is the same and the scanning line for starting the scanning is changed in a set of subfields. In the present embodiment, the method of canceling the DC bias component by combining two consecutive subfields has been described, but the subfields to be combined need not be continuous. Also, the case where the scanning period is divided into the first half and the second half has been described as an example. However, the scanning period may be divided into three or more, and the first maintenance having a wide width applied to one of the two subfields in a set is performed. The pulse Psf only needs to have a width that cancels the DC bias component of each scanning line in the two subfields.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 7 is a diagram showing a third embodiment of the method of driving the plasma display panel according to the present invention, and is a timing chart showing the state of the pulse waveform applied to each electrode.

As shown in FIG. 7, in this embodiment, the entire scanning electrode is divided into a plurality of sub-scanning electrode groups (first sub-scanning electrode group to L-th sub-scanning electrode group) in the scanning line direction. The width of the scan base pulse Pw in the scan electrode group is set to be equal, and the width of the first sustain pulse Psf is set to be equal.

Then, as in the first embodiment, the sum of the widths of the scan base pulses Pb in each scan electrode becomes equal, and the sum of the widths of the first sustain pulses Psf in each scan electrode becomes equal. Thus, two predetermined sub-fields are combined for each sub-scanning electrode group.

It is to be noted that the width of the first sustaining pulse Psf is set to a width that can cancel the DC bias due to the scanning base pulse Pb and suppress the generation of dendrites due to the DC bias in the first embodiment. This is the same as the embodiment.

In this manner, similarly to the first embodiment, it is possible to prevent an unstable operation due to the separation between the write discharge and the sustain discharge period, and to reduce the DC current generated between the scan electrode and the sustain electrode. Generation of dendrites due to bias can be suppressed.

FIG. 8 is a block diagram showing a configuration of a third embodiment of the driving apparatus for a plasma display panel according to the present invention.

As shown in FIG. 8, the PDP driving apparatus according to the present embodiment has a configuration in which sustain drivers 54 for outputting sustain pulses to the scan electrodes are provided for each sub-scan electrode group. The other configuration is the same as that of the first embodiment, and the description is omitted. According to the PDP driving apparatus of the present embodiment, the sub-scanning electrode group is connected to one sustain driver 5.
4, the number of sustain drivers 54 is changed to the first.
Can be significantly reduced as compared with the embodiment. Therefore, an increase in circuit scale is suppressed.

Next, the effects of the present embodiment will be described below using specific examples.

The number of scan electrodes of the PDP is set to 480, and they are divided into 30 sub-scan electrode groups, and a scan base pulse Pb and a first sustain pulse Psf are applied to each group. At this time, the width of the scan pulse Pw is 3 μs, the width of the scan base pulse Pb is 54 μs, and the scan base pulse voltage is −100 V. Further, the potential of the sustain pulse Ps is set to +1
At 70 V, the width of the first sustain pulse Psf is calculated using the above equation (2) in order to cancel the DC component due to the scanning base pulse, and the first sustain pulse Psf is applied based on the calculated value. (The sum of the widths of the first sustain pulses of the two subfields forming a pair is 110 μs).

As a result of the evaluation of the life of the PDP under the above conditions, no generation of dendritic projections due to electromigration was observed, and stable life characteristics could be obtained.
Further, the margin of the driving voltage is wider than that of the conventional driving method.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to the drawings.

FIG. 9 is a diagram showing a fourth embodiment of the method of driving the plasma display panel according to the present invention, and is a timing chart showing the state of the pulse waveform applied to each electrode.

As shown in FIG. 9, in the method of driving the PDP of the present embodiment, the widths of the scan base pulses Pb applied to the scan electrodes are all equal. The other driving method and the configuration of the driving device are the same as those of the third embodiment, and the description thereof is omitted.

According to the driving method of the present embodiment, since the width of the scanning base pulse Pb can be reduced as compared with the driving method of the third embodiment shown in FIG. 7, the DC bias component is reduced. The width of the first sustain pulse Psf can be reduced.

If the width of the first sustain pulse Psf is too wide, discharge is likely to occur, and erroneous discharge may occur. According to the driving method of the present embodiment, erroneous discharge can be prevented by shortening the width of the first sustain pulse Psf.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to the drawings.

FIG. 10 is a diagram showing a fifth embodiment of the method of driving the plasma display panel according to the present invention, and is a timing chart showing the state of the pulse waveform applied to each electrode.

As shown in FIG. 10, in the present embodiment, a plurality of sub-scan electrode groups (first
Sub-scanning electrode group to L-th sub-scanning electrode group).
Correspondingly, the entire sustain electrode is divided into a plurality of sub-sustain electrode groups (first sub-sustain electrode group to L-th sub-sustain electrode group). Note that pulse waveforms Wu _{1 to} Wu _L are commonly applied to the first sub sustain electrode group to the L th sub sustain electrode group, respectively. Further, similarly to the third embodiment, the width of the scan base pulse Pw in the sub-scan electrode group is set to be equal, and the width of the first sustain pulse Psf is set to be equal.

In the first embodiment, the sustain pulse Ps is applied to each sub-scanning electrode group at the same timing.
However, in the present embodiment, the application of the sustain pulse Ps is started immediately after the application of the first sustain pulse Psf to each sub-scanning electrode group. Note that the number of sustain pulses applied to each sub-scanning electrode group may be different from each other, and the width of the scanning base pulse Pb applied to each scanning electrode may be equal as in the fourth embodiment.

FIG. 11 is a block diagram showing a configuration of a driving apparatus for a plasma display panel according to a fifth embodiment of the present invention.

As shown in FIG. 11, the PDP driving apparatus of the present embodiment has a configuration in which sustain drivers 62 for outputting sustain pulses to sustain electrodes are provided for each sub sustain electrode group. The other configuration is the same as that of the second embodiment, and the description is omitted.

According to the driving method of the PDP of the present embodiment, the interval between all sustain pulses Ps becomes narrow, and the first sustain pulse is applied even when the sustain pulse Ps applied next to the first sustain pulse Psf is applied. The active particles generated at the time of application of can be used. As a result, the sustain discharge characteristics are further improved.

Further, since the weighting of the number of sustain pulses is changed in each sub-scanning electrode group and the sustaining pulse can be applied even when the other sub-scanning electrode groups are in the scanning period, the sustaining period can be shortened. .

Next, the effect of this embodiment will be described with reference to FIG.

FIG. 12 is a diagram for explaining the effect of the fifth embodiment of the method for driving a plasma display panel according to the present invention, and is a timing chart showing how the sustain period is shortened by a combination of subfields.

FIG. 12A shows a conventional driving method. Two subfields have 2a (a is a natural number) and a sustain pulses, respectively.

FIG. 12B is a diagram showing the driving method according to the present embodiment, in which the scan electrode and the sustain electrode are divided into ten sub-scan electrode groups and sub-sustain electrode groups, respectively, and the upper half and the lower half of the figure are divided. The weight of the maintenance period is replaced. As a result, the sustain period can be shortened by the number of a sustain pulses as compared with the conventional driving method. Here, 2
Although one subfield has been illustrated, it is expected that the maintenance period can be further reduced by selecting an efficient combination in all the subfields.

Further, if the shortened time is allocated to the scanning period, the width of the scanning pulse can be widened, so that the writing characteristics can be improved. Further, if the shortened time is allocated to the sustain period, the number of sustain pulses can be increased, so that the brightness of the PDP can be increased.

[0127]

Since the present invention is configured as described above, the following effects can be obtained.

During the scanning period in the scan sustaining-separation type driving sequence, a scan pulse is applied to each scan electrode in a predetermined order while being superimposed on a scan base pulse, and a data pulse is applied to a predetermined data electrode. After writing the video data selectively and applying the scan pulse approximately a fixed time later, the scan pulse is set to a width opposite to the polarity of the scan pulse and to cancel the DC component due to the scan base pulse in the total of two subfields. By applying the first sustain pulse to the scan electrode, unstable operation due to separation between the write discharge and the sustain discharge period is prevented, and the generation of dendrites due to a DC bias generated between the scan electrode and the sustain electrode is prevented. Is suppressed.

Further, the entire scanning electrode is divided into a plurality of sub-scanning electrode groups in the scanning line direction.
In one of the two subfields, video data is sequentially written to each scanning line from one end of the plasma display panel to the other end, and the other of the two subfields is the other end of the plasma display panel. By writing video data in order from one end to the other end, a circuit for applying a sustain pulse to the scan electrodes can be shared for each sub-scan electrode group, thereby suppressing an increase in circuit scale. .

Further, the entire sustain electrode is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and each of the sub-scan electrode groups and the sub-sustain electrode groups is immediately after the first sustain pulse is applied. By starting the sustain discharge, the sustain discharge can be performed more stably, so that the sustain discharge characteristics are improved.

Further, by outputting the scan base pulses applied to all the scan electrodes with the same width, the scan base pulse can be shortened, and accordingly, the width of the first sustain discharge pulse is also shortened. can do.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of a driving device for a plasma display panel of the present invention.

FIG. 2 is a block diagram showing a configuration example of a data electrode driver, a sustain electrode driver, and a scan electrode driver shown in FIG.

FIG. 3 is a diagram illustrating a first embodiment of a method of driving a plasma display panel according to the present invention, and is a timing chart illustrating a state of a pulse waveform applied to each electrode.

FIG. 4 is a graph showing a capacitance between a scan electrode and a sustain electrode (one set) after a DC voltage is applied between the scan electrode and the sustain electrode for a predetermined time.

5 is a diagram showing a state of wall charges generated by the driving method shown in FIG. 3, and is a schematic diagram showing a state before and after application of a scanning pulse and a first sustain pulse.

FIG. 6 is a diagram showing a second embodiment of the driving method of the plasma display panel according to the present invention, and is a timing chart showing a state of a pulse waveform applied to each electrode.

FIG. 7 is a diagram illustrating a third embodiment of the method of driving the plasma display panel according to the present invention, and is a timing chart illustrating a state of a pulse waveform applied to each electrode.

FIG. 8 is a block diagram showing the configuration of a third embodiment of the plasma display panel driving device of the present invention.

FIG. 9 is a diagram showing a fourth embodiment of a method of driving a plasma display panel according to the present invention, and is a timing chart showing a state of a pulse waveform applied to each electrode.

FIG. 10 is a diagram showing a fifth embodiment of the method of driving the plasma display panel according to the present invention, and is a timing chart showing the state of the pulse waveform applied to each electrode.

FIG. 11 is a block diagram showing a configuration of a driving apparatus for a plasma display panel according to a fifth embodiment of the present invention.

FIG. 12 is a diagram illustrating the effect of the fifth embodiment of the method for driving a plasma display panel according to the present invention, and is a timing chart illustrating a manner in which a sustain period is shortened by a combination of subfields.

FIG. 13 is a perspective sectional view of a display cell showing one configuration example of an AC discharge memory type plasma display panel.

14 is a plan view showing a schematic configuration of a plasma display panel formed by arranging the display cells shown in FIG. 13 in a matrix.

FIG. 15 is a diagram illustrating a conventional method of driving a plasma display panel, and is a waveform diagram illustrating a state of a pulse waveform applied to each electrode.

FIG. 16 is a diagram showing a driving method of a conventional plasma display panel, and is a time chart illustrating a subfield method for performing multi-tone display.

FIG. 17 is a schematic view showing a growth mechanism of dendritic projections caused by a DC bias.

FIG. 18 is a waveform chart showing an example of a conventional driving method of a plasma display panel for preventing electromigration.

FIG. 19 is a graph showing a relationship between a time difference from the occurrence of a discharge in a display cell to the next application of a discharge pulse to a discharge delay time.

[Explanation of symbols]

 Reference Signs List 1 PDP 2 Data electrode driver 3 Scan electrode 4 Sustain electrode 5 Scan electrode driver 6 Sustain electrode driver 7 Data electrode 8 Interface circuit 9 Data power supply 10 Sustain power supply 11 Scan power supply 12 Reset power supply 13 Erase power supply 21 Data driver 51 Scan driver 52, 54 , 61, 62 Maintenance driver 53 Reset driver

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/66 101 H04N 5/66 101B F-term (Reference) 5C058 AA11 BA02 BA03 BA04 BA05 BB01 5C080 AA05 BB05 DD04 DD05 DD06 EE29 FF13 GG08 HH05 JJ02 JJ04 JJ05 JJ06 5C094 AA02 AA03 AA15 AA24 AA37 AA54 AA55 BA31 CA19 DB02 DB04 DB10 EB02 EC04 GA10 JA20

Claims (16)

[Claims] 1. A scan sustaining separation for displaying a desired image while displaying a multi-gradation by a subfield method on an AC discharge memory type plasma display panel including a plurality of display cells arranged in a grid. A plasma display panel driving method, wherein a scan pulse is applied to each scan electrode in a predetermined order while being superimposed on a scan base pulse within a scan period in the scan sustaining / separation type drive sequence, and The video data is selectively written by applying a data pulse to the data electrode, and after approximately a fixed time after the application of the scanning pulse, the scanning is performed in the opposite polarity to the scanning pulse and in the total of two subfields. A first sustain pulse having a width set to cancel a direct current component caused by a base pulse is applied to the scan electrode, and the sustain voltage is applied to the scan electrode. The driving method of a plasma display panel for the first sustain discharge between the. 2. One of the two sub-fields sequentially writes video data on each scanning line from one end of the plasma display panel to the other end thereof, and the other of the two sub-fields. 2. The method according to claim 1, wherein video data is sequentially written to each scanning line from the other end to the one end of the plasma display panel. 3. One of the two sub-fields sequentially writes video data to each scanning line from one end of the plasma display panel to the other end thereof, and the other of the two sub-fields. Then, the entire scan electrode is divided into two in the scan line direction, and video data is written in order from an intermediate scan line of the plasma display panel toward the other end, and then the intermediate portion is formed from one end of the plasma display panel. 2. The method of driving a plasma display panel according to claim 1, wherein the video data is sequentially written toward the scanning line. 4. The method of driving a plasma display panel according to claim 3, wherein the entire scan electrode is divided into three or more in the scan line direction. 5. The sub-scanning electrode group is divided into a plurality of sub-scanning electrode groups in the scanning line direction, and one of the two sub-fields is one end of the plasma display panel for each of the sub-scanning electrode groups. Video data is sequentially written to each scanning line from one side to the other end side, and video data is sequentially written from the other end side to the one end side of the plasma display panel in the other of the two subfields. Item 6. A method for driving a plasma display panel according to Item 1. 6. The first sustaining pulse is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and the first sustain pulse is provided for each of the sub-scan electrode groups and the sub-sustain electrode groups. 6. The driving method of a plasma display panel according to claim 5, wherein the sustain discharge is started immediately after the application of the voltage. 7. The width of the scanning base pulse and the first
7. The driving method of a plasma display panel according to claim 1, wherein the sustain pulse width of each of the two sub-fields is made equal for each scanning electrode. 8. The scanning base pulse according to claim 1, wherein the width of the scanning base pulse applied to all the scanning electrodes is made equal.
The driving method of the plasma display panel according to the above item. 9. A scan-maintenance-separation-type plasma display panel comprising a plurality of display cells arranged in a lattice pattern and displaying a desired image while displaying multiple gradations using a subfield method. A driving apparatus for a plasma display panel, wherein a scan pulse is applied to each scan electrode in a predetermined order while being superimposed on a scan base pulse, and a predetermined data electrode The video base is selectively written by applying a data pulse to the scan base pulse, and after approximately a fixed time after the application of the scan pulse, the scan base pulse has a polarity opposite to that of the scan pulse and is the sum of two subfields. A first sustaining pulse set to a width that cancels out the direct current component due to In apparatus for driving a plasma display panel having a scan electrode driver for making the first sustain discharge. 10. The scan electrode driver applies the scan pulse to one of the two subfields sequentially from one end of the plasma display panel to the other end of the plasma display panel to each scan electrode. 10. The plasma display panel driving device according to claim 9, wherein, in the other of the two subfields, the scan pulse is sequentially applied to each scan electrode from the other end to the one end of the plasma display panel. 11. The scan electrode driver applies one of the two sub-fields to the scan electrodes in order from one end of the plasma display panel to the other end of the plasma display panel, In the other of the two subfields, the entire scan electrode is divided into two in the scan line direction, and the scan pulse is applied in order from the middle scan electrode of the plasma display panel toward the other end. 10. The driving apparatus for a plasma display panel according to claim 9, wherein the scanning pulse is applied in order from one end of the plasma display panel toward the intermediate scanning electrode. 12. The driving apparatus of claim 11, wherein the scan electrode driver divides the entire scan electrode into three or more in the scan line direction. 13. The scan electrode element driver divides the entire scan electrode into a plurality of sub-scan electrode groups in the scan line direction, and for each of the sub-scan electrode groups, one of the two sub-fields The scanning pulse is sequentially applied to each scanning line from one end of the plasma display panel toward the other end, and the other of the two sub-fields is applied from the other end to the one end of the plasma display panel. 10. The driving device for a plasma display panel according to claim 9, wherein the scanning pulses are applied in order toward the plasma display panel. 14. The sustain electrode is divided into a plurality of sub-sustain electrode groups corresponding to the sub-scan electrode groups, and a sustain discharge is performed immediately after applying the first sustain pulse for each of the sub-sustain electrode groups. And a sustain electrode driver for applying a sustain pulse to the sustain electrode for performing the sustain pulse. The scan electrode driver performs a sustain discharge immediately after applying the first sustain pulse for each of the sub-scan electrode groups. 14. The driving device for a plasma display panel according to claim 13, wherein a sustain discharge pulse is applied. 15. The scan electrode driver according to claim 9, wherein the width of the scan base pulse and the first sustain pulse width are equal for each scan electrode in the total of the two subfields. The driving device for a plasma display panel according to claim 1. 16. The driving apparatus for a plasma display panel according to claim 9, wherein the scan electrode driver applies a scan base pulse having the same width to all scan electrodes.