JPH09244578A - Plasma display device and its driving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the driving time of one subframe. SOLUTION: The display panel is provided with plural X electrodes, plural scanning Y electrodes and plural address electrodes, which intersect with the Y electrodes. The device is driven during the address period in which electrostatic discharges are selectively conducted between the Y electrodes and the address electrodes for lighting while the Y electrodes are scanned and during the sustaining electrostatic discharging period in which lighting is sustained by conducting sustained discharges between the X and Y electrodes against the cells that are lighted during the address period succeeding an address period. Note that in the panel, the address electrodes are shared and the Y electrodes are divided at least into a first panel section 321 and a second panel section 322. When a driving is conducted against the section 321 during the address period, a driving is conducted against the section 322 during the sustained discharge period. Moreover, when a driving is conducted against the section 321 in the sustained discharge period, a driving is conducted against the section 322 during the address period.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel (PDP) and a driving method thereof for reducing the address period and increasing the number of gradations.

[0002]

2. Description of the Related Art A PDP device for displaying a predetermined image by generating a plasma discharge between two glass substrates has been developed as a next-generation display device capable of realizing a thin and clear screen. ing.

As one of the PDP devices, an alternating current (A
There is a CDP type PDP. The basic principle of the AC type PDP is that a high voltage write pulse is first applied between the electrodes to cause a discharge, and wall charges are generated due to the discharge. By alternately applying, the discharge is repeated again according to the sum voltage of the wall charge voltage and the sustain discharge voltage.

AC type PDPs have various electrode configurations, but in the case of a color PDP for displaying gray scales,
The fluorescent substance in the discharge cell is excited by the ultraviolet rays generated by the discharge, and since this fluorescent substance is generally weak against the ion bombardment associated with the discharge, a three-electrode structure utilizing surface discharge is generally used. Then, there are various variations in how to arrange the three electrodes on the two glass substrates.
In addition, regarding the method of extracting visible light from the phosphor, there are a transmission type and a reflection type, and there are variations such as a barrier that divides the discharge cell in four directions and one that is provided only on one side.

In this specification, as an example, two electrodes for sustaining discharge are provided on one substrate, and a third electrode (address electrode) for performing address discharge is provided on the other substrate on the other side. An example will be described in which two electrodes are provided so as to intersect with each other, a barrier is provided only in parallel to the address electrodes, and visible light is further reflected and taken out. However, as described above, various modifications are possible.

FIG. 6 shows an AC type PD having a surface discharge with its three electrodes.
It is a schematic plan view of P. 7 and 8 are schematic sectional views thereof. As shown in FIG. 6, the comb-shaped X electrode 1
2 and a plurality of Y electrodes 14 are provided alternately in parallel in the horizontal direction. Then, a plurality of address electrodes 16 are provided orthogonally thereto. Barriers 18 are provided in parallel on both sides of the address electrode 16, and a pair of a pair of X electrode 12, Y electrode 14 and address electrode 16 sandwiched by the barrier 18 constitutes a cell 20.

The cross sectional structures of these are as shown in FIGS. 7 and 8. The address electrode 16, the phosphor 22 and the barrier 18 are laminated on the rear glass substrate 21. In addition, a sustain electrode 28 including a transparent electrode 24 and a low-resistance (Cu or Cr) bus electrode 25 on the front glass substrate 23.
(X electrode 12 and Y electrode 14), a dielectric layer 26 and a MgO layer 27 as a protective layer thereof are laminated as shown in the figure.
Then, the phosphor 2 is generated by the ultraviolet rays generated by the discharge.
Visible light generated by being excited by 2 passes through the transparent electrode 24 as reflected light 30 and is emitted from the front glass substrate 23. Adjacent RGB cells enable color display.

FIG. 9 is a block diagram showing a peripheral circuit for driving the PDP. The PDP described in FIGS. 1 to 3
An X common driver 120 that drives each electrode of the panel 32,
A Y scan driver 140, a Y common driver 144, and an address driver 160 are provided respectively.
Further, the control circuit 34 that controls these drivers includes
The dot clock 1, the display data 2, the vertical synchronizing signal 3, and the horizontal synchronizing signal 4 are supplied. Display data control unit 36
Then, it has a frame memory 38 for storing data corresponding to an image to be displayed from the display data 2, and the panel drive control unit 40 has a Y scan driver control unit 41.
And a common driver control unit 42.

FIG. 10 is a conventional general drive waveform diagram of an AC PDP. The AC PDP is driven by a combination of subfields including a reset period, an address period, and a sustain discharge period. In the reset period, all the write pulses are applied to the X electrodes all at once, and all the cells are turned on and off to reset. Then, in the subsequent address period, while scanning the Y electrode, the address pulse is applied to the address electrode 16 to the electrode corresponding to the cell to be lighted. As a result, a high potential difference (150 + 50 = 200 v in the example of FIG. 10) is generated between the address electrode 16 and the Y electrode 14, and plasma discharge occurs. Using this as a pilot fire, the discharge also moves between the X electrode 12 and the Y electrode 14 (also 200 V is generated), and the corresponding X
The amount of wall charges capable of sustaining discharge later is accumulated on the surface of the MgO layer 27 on the electrodes and the Y electrodes. In the address period, it is necessary to discharge all the Y electrodes 14, which requires a considerable amount of time.

In the sustain discharge period following the address period, the sustain pulse Vs is applied between the Y electrode 14 and the X electrode 12.
Is applied alternately, the voltage of the sustain pulse Vs is further added to the potential due to the charges accumulated during the address period in the cell being lit, and the discharge is alternately performed between both electrodes.
Therefore, during the sustain discharge period, sustain pulses are applied to all Y electrodes and all X electrodes. When this sustain discharge period is lengthened, it looks bright to the human eye, and when shortened, it looks dark. That is, the brightness is adjusted depending on the sustain discharge period.

FIG. 11 is a time chart for one frame, and shows that an image for one frame can be displayed by repeating the subfield of FIG. 10 eight times. That is, as described with reference to FIG. 10, each subfield includes a reset period, an address period, and a sustain discharge period, and the sustain discharge period has a ratio of 1: 2: 4: 8: 16: 32: 64: 128, for example. Has been done. As a result, a maximum of 256 gradations can be displayed by combining eight subfields. Therefore, each of the eight subfields has a reset period having the same length and a sustain discharge period having a different length from the address period.

[0012]

For example, in the case of the 60 Hz non-interlace system, the time for one frame is 1 /
It is 16.6 ms, which is 60 seconds. However, if the number of sub-frames needs to be increased as the number of gradations is further increased, or if the number of Y scan electrodes is increased as the screen size is further increased, driving within one frame time is required. Is expected to be difficult. Moreover, in the subfield having the shorter sustain discharge period, the address period is actually considerably longer than the sustain discharge period and the reset period.

Therefore, an object of the present invention is to provide a driving method of a PDP device and a device therefor capable of coping with multi-gradation and screen enlargement.

Another object of the present invention is to allow many subfields to fit within one frame without shortening the reset period or the time required for scanning.
It is to provide a driving method of a DP device and the device.

[0015]

SUMMARY OF THE INVENTION The above object is to provide a plurality of Xs.
A panel is provided with an electrode, a plurality of Y electrodes for scanning, and a plurality of address electrodes provided to intersect with the Y electrodes, and the Y electrodes and the address electrodes are formed while scanning the Y electrodes. An address period in which the cells are selectively discharged and lighted in the meantime, and a sustain discharge period in which a sustain discharge is generated between the X and Y electrodes for cells that are lighted in the address period subsequent to the address period to maintain lighting. In the driven plasma display device and the driving method thereof, the panel comprises:
The address panel is provided in common and at least divided into a first panel section having a first plurality of Y electrodes and a second panel section having a second plurality of Y electrodes. With respect to the second panel part, the second panel part is driven with the sustain discharge period, and the second panel part is driven with the second discharge part during the sustain discharge period. This is achieved by providing a plasma display device and a driving method thereof, which is provided with a driving device for driving the panel section in the address period.

The driving time can be shortened by performing the sustain discharge driving on the other panel portion while the one panel portion is driven on the address. Therefore, more sub-frame periods can be provided, so that it is possible to deal with multiple gradations. Moreover, since more Y electrodes can be scanned, it is possible to cope with a large screen.

Further, in the above plasma display device, since the address electrodes are commonly used in the first and second panel portions, one panel portion drives the address electrodes during the address period to perform the writing operation. During this period, the sustain voltage is applied to the X and Y electrodes in association with the driving of the sustain discharge period of the other panel section, so it is necessary to avoid the occurrence of discharge in the other panel section by the common address electrode. There is.

Therefore, in the driving apparatus or the driving method of the present invention, during the address period, a reference potential or a selection potential is applied to the address electrode to apply a scan potential to the Y electrode at the time of scanning so that the two electrodes are connected to each other. A discharge is generated, and a sustain voltage is alternately applied between the X and Y electrodes during the sustain discharge period,
A sustain discharge is generated between both electrodes, the reference potential and the selection potential are potentials between the sustain voltages, and a discharge is generated between the address electrode and the X or Y electrode during the sustain discharge period. It is characterized in that a voltage lower than the voltage is applied.

Further, in order to display an image by repeating the address period and the sustain discharge period, a driving period for resetting all cells is required before the address period. Therefore, the driving device or the driving method of the present invention performs driving for resetting all cells in the reset period preceding the address period, and when the first or second panel unit is in the reset period, the other The panel portion of is characterized by being in a rest state.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. However, the technical scope of the present invention is not limited to such an embodiment.

FIG. 1 is a schematic block diagram of the PDP of this embodiment. The same parts shown in FIG. 9 are denoted by the same reference numbers. The structure of the panel of the PDP of FIG. 1 is the same as that shown in FIGS. 6, 7 and 8 and will not be described again here. 9 is different from FIG. 9 in that the panel is vertically divided into two parts, and is composed of a first panel part 321 and a second panel part 322. For each panel part, the X drivers 121, 122 and the Y scan driver 1 are provided.
41, 142 and Y common drivers 1 and 2 are provided. The method of dividing the first and second panel parts 321 and 322 can be changed as appropriate. What is needed is that the Y electrodes to be scanned are divided into two groups. Therefore, although the structure of the electrodes becomes complicated, it is possible to make the odd-numbered Y electrodes the first panel portion and the even-numbered Y electrodes the second panel portion. However, in order to simplify the structure, it is desirable to divide the upper and lower parts into two as shown in FIG.

FIG. 2 is a time chart for one frame when driving the PDP constructed as shown in FIG. As shown in this example, the first panel unit 321 has only half the number of Y electrodes, and the number of Y electrodes to be scanned is half, so the address period is half that of the conventional one. For example, in the subfield 1, on the first panel portion 321 side, the reset period is in the period t1 and the address period is in the period t2. And the required rest period t3
After that, in the period t4, sustain pulses are alternately applied between the Y electrodes and the X electrodes belonging to the first panel unit 321. Therefore, the Y1 scan driver 141 and the X1 driver 121
The sustain pulse is applied by.

On the other hand, the second panel portion 322 side is reset during the period t3, and writing is performed while the first panel portion 321 side is performing the sustain discharge during the period t4. Therefore, the period t4 becomes the address period. And
After pausing during the reset period t5 of the first panel unit 321, sustain discharge is performed during the address period t6 of the first panel unit 321.

As described above, basically, the address period and the sustain discharge period are alternately repeated in the first and second panel portions. Therefore, when viewed within the period of one subfield, the total address period of the first and second panel parts is
The time is the same as the address period in the conventional case, and since the other sustain discharge is performed during each address period, the sustain discharge period is unnecessary. Of course, the lisset period is 2
However, there is no problem because the reset period itself is a very short period. Depending on the length of each address period, if the other sustain discharge period falls within the address period, the length of each subfield will be shortened by the amount of that sustain discharge period, and the other sustain discharge period will be shorter than the address period. Even if the period is longer, the length of the sub-feel is only increased by the lengthened period.

Therefore, it is apparent that the present invention takes a shorter time when compared with the same number of sub-frames as in the conventional case when viewed in one frame as a whole. Therefore, the number of sub-frames can be increased by that amount to handle more gradations, and also a larger screen can be handled.

FIG. 3 shows a drive waveform diagram in one subfield. The operation will be described in time. The difference from FIG. 10 of the conventional example is that the reference voltage of the address electrode is 50.
This is a high point.

First, in the period t1, on the side of the first panel portion 321, 3 is applied to the X1 electrode as a full writing pulse.
A high voltage of 30v is applied. As a result, all cells are discharged regardless of the previous display state. Immediately after that, the X1 electrode becomes 0 v, and the voltage of the wall charge exceeds the discharge start voltage in all cells to start discharge. Since this discharge has no potential difference between the electrodes, wall charges are not formed thereby, and the space charges self-neutralize to terminate the discharge. By this self-erasing discharge, all cells in the first panel portion 321 are brought into a uniform state with no wall charges and are reset.

Next, in a period t2, while applying a negative voltage scan pulse VY (-150v) to the Y1 electrode, the address pulse V is applied to the address electrode 16 according to the display data.
a (60v) is applied. Therefore, 200 V is applied between the Y1 electrode and the address electrode, and a discharge is generated.
Then, by using it as a pilot fire, a discharge is generated between the Y1 electrode and the X1 electrode, and wall charges are accumulated.

The period t2 corresponds to the sustain discharge period in the second panel section 322. Therefore, the sustain pulse Vs is alternately applied between the X2 electrode and the Y2 electrode. At this time, on the side of the second panel portion 322, the address electrode to which the address pulse Va (60v) for writing in the first panel portion 321 is applied and the sustain pulse V in the second panel portion 322 are applied.
It is necessary to avoid the occurrence of discharge between the X2 and Y2 electrodes to which s is applied. In the example of this embodiment,
By setting the address pulse Va of the address electrode to 60v and the reference voltage to 50v, which are higher than those in the prior art, such discharge is avoided.

That is, as shown in the sectional view of the panel of FIG. 7, in the period t2, the writing discharge needs to be generated between the address electrode 16 and the Y electrode 14 in the first panel portion 321. On the other hand, in the second panel portion 322, the same address electrode 16 is used, but it is necessary to repeat the surface discharge between the X electrode 12 and the Y electrode 14. Therefore, in the second panel portion 322, it is necessary to avoid generating a discharge between the address electrode 16 and the X, Y electrodes 12, 14.

FIG. 4 is a diagram showing the relationship between the potential of the address electrode and the potential of the X and Y electrodes which are the sustain electrodes. When both potentials correspond to a certain area (stable operation area in the figure) where a predetermined relationship is established, there is a characteristic that discharge between both electrodes does not occur. That is, if the reference voltage of the X and Y electrodes and the voltage of the sustain pulse Va are not extremely low or high, the discharge can be avoided by setting the voltage of the address electrode in the intermediate region between them. Therefore, the second panel portion 322 has a voltage relationship that enters the stable operation area, and the selected address electrode in the first panel portion 321 has a voltage relationship that enters the stable operation area. You just have to select the voltage.

Therefore, in the example of FIG. 3, the reference potential (OFF potential) of the address electrode is raised from 0v to 50v. By doing so, no discharge is generated between the address electrode and the sustain discharge voltages 0v and Vs (180v) on the second panel 322 side, and the sustain discharge is not affected.

Returning to FIG. 3, during the period t3, the first panel section 321 is suspended, and the second panel side 322 is in the reset period. The operation is equivalent to that described above. Then, in the period t4, the sustain discharge period is in the first panel portion and the address period is in the second panel portion.

FIG. 5 is an example of another drive waveform. The difference from FIG. 3 is that the reference voltage of the address electrode is returned to 0v, and the reference voltage of the X and Y electrodes in the sustain discharge period is lowered by about half of the sustain pulse Vs to −90v, + 90v. That is, although the voltage when the address pulse of the address electrode is applied is lowered, X, which is the sustain electrode,
The voltage on the Y electrode side is also reduced accordingly. Therefore,
Similarly, no discharge occurs between the address electrodes and the sustain electrodes (X, Y electrodes) during the sustain period. Since the other points are the same as those in the case of FIG. 3, the description will not be repeated.

In the above-mentioned embodiment, the sustain electrodes are provided on one substrate, the address electrodes are provided on the other substrate, and the barriers are provided in parallel with the address electrodes. However, as described above, according to the present invention, when the address period and the discharge sustaining period are basically required, the panel is divided into two and the address period and the discharge sustaining period are provided even if various modified structures are required. By alternately performing the above, the period required for the subframe can be shortened.

[0036]

As described above, according to the present invention, P
The DP can be divided into two panel portions, and the address period and the sustain discharge period can be alternately performed in each panel portion. Therefore, the period of each subframe can be shortened, and as a result, the period of a frame composed of a plurality of subframes can also be shortened. Therefore, even if the period of one frame is fixedly limited, more subframes can be inserted, or the panel can be made larger and more Y electrodes can be provided. Therefore, it is possible to cope with more gradations or larger screens.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a PDP according to an embodiment.

FIG. 2 is a time chart diagram for one frame according to the embodiment.

FIG. 3 is a drive waveform diagram (1) according to the embodiment.

FIG. 4 is a relationship diagram between the potential of an address electrode and the potential of a sustain electrode.

FIG. 5 is a drive waveform diagram (2) according to the embodiment.

FIG. 6 is a schematic plan view of an AC PDP.

FIG. 7 is a schematic sectional view of an AC PDP.

FIG. 8 is a schematic sectional view of an AC PDP.

FIG. 9 is a block diagram of a peripheral circuit for driving a conventional PDP.

FIG. 10 is a conventional general drive waveform diagram of an AC PDP.

FIG. 11 is a conventional time chart for one frame.

[Explanation of symbols]

12 X electrodes 14 Y electrodes 16 address electrodes 121, 122, 141, 142, 144, 160 Driving device 321 First panel part 322 Second panel part

Claims (6)

[Claims] 1. A panel having a plurality of X electrodes, a plurality of Y electrodes for scanning, and a plurality of address electrodes intersecting with the Y electrodes, and scanning the Y electrodes. An address period in which the Y electrode and the address electrode are selectively discharged for lighting, and a sustain discharge is generated between the X and Y electrodes in a cell that is lit in the address period following the address period to illuminate. In a plasma display device driven by a sustain discharge period for maintaining the above, the panel includes a first panel portion having the address electrodes in common and a first plurality of Y electrodes, and a second plurality of panel electrodes. At least divided into a second panel portion having a Y electrode, and when the first panel portion is driven in the address period, the second panel portion is driven in the sustain discharge period, first A plasma display apparatus characterized in that a drive unit for driving the address period with respect to said second panel when the panel unit for driving the sustain discharge period. 2. The plasma display device according to claim 1, wherein the driving device applies a reference potential or a selection potential to the address electrode during the address period to apply a scan potential to a Y electrode during scanning, A discharge is generated between the electrodes, and during the sustain discharge period, a sustain voltage is alternately applied between the X and Y electrodes to generate a sustain discharge between both electrodes, and the reference potential and the selection potential are set to the sustain voltage. It is characterized in that a voltage, which is between the voltages, is applied between the address electrode and the X or Y electrode during the sustain discharge period, which is lower than the voltage at which discharge is generated. 3. The plasma display device according to claim 1, wherein the driving device performs driving for resetting all cells during a reset period preceding the address period, and the first or second panel unit During the reset period,
The other panel is characterized by being in a resting state. 4. A panel having a plurality of X electrodes, a plurality of Y electrodes for scanning, and a plurality of address electrodes provided so as to intersect the Y electrodes, wherein the Y electrodes are scanned. An address period in which the Y electrode and the address electrode are selectively discharged for lighting, and a sustain discharge is generated between the X and Y electrodes in a cell that is lit in the address period following the address period to illuminate. In a plasma display device driven with a sustain discharge period for maintaining the above, a first panel portion having a plurality of first Y electrodes is driven in the address period and has a plurality of second Y electrodes. A first drive period for driving the sustain discharge period for a second panel unit, and a drive for the sustain discharge period for the first panel unit, and for the second panel unit Of the address period The driving method of a plasma display device which comprises a second drive period for the dynamic. 5. The driving method of the plasma display device according to claim 4, wherein during the address period, a reference potential or a selection potential is applied to the address electrodes according to display data, and a scan potential is sequentially applied to the Y electrodes for scanning. , A discharge is generated between the Y electrode to which the scan potential is applied and an address electrode to which the selection potential is applied, and a reverse polarity is alternately maintained between the X electrode and the Y electrode during the sustain discharge period. A voltage is applied to generate a sustain discharge between both electrodes, and the reference potential, the selection potential, and the sustain voltage are lower than the voltage required to generate the discharge between the X or Y electrode and the address electrode during the sustain discharge period. Is set to be applied. 6. The method for driving a plasma display device according to claim 4, wherein the first driving period and the second driving period are repeated, and the first driving period and the second driving period are repeated. The second panel unit is reset, and a reset period in which the first panel unit is reset is included between the second driving period and the first driving period.