JP2005037605A - Driving method of plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving method of a plasma display panel by which write-in operation is stabilized and thereby the unlighting of a cell can be suppressed and display characteristic can be improved. <P>SOLUTION: In the driving method of the plasma display panel in which one field period is composed of a plurality of sub-fields having a write-in period and a sustain period, maintenance operation of the sustain period in at least one sub-field among a plurality of sub-fields and initialization operation of an initialization period of a subfield following the above-mentioned subfield are simultaneously performed and a strong discharge initialization period is provided at the head of the write-in period in at least one sub-field among a plurality of sub-fields. Thereby strong discharge is made to occur before the write-in period to more stabilize the write-in operation and consequently unlighting of the cell can be suppressed and the display characteristic can be improved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving method of a plasma display panel used as a thin, lightweight display device having a large screen.
[0002]
[Prior art]
FIG. 5 shows a plasma display panel (hereinafter referred to as a panel). As shown in FIG. 5, the panel 1 is configured by arranging a glass front substrate 2 and a rear substrate 3 to face each other so as to form a discharge space therebetween. A plurality of scan electrodes 4 and sustain electrodes 5 are formed in parallel with each other on the front substrate 2, and a dielectric layer 6 is formed so as to cover the scan electrodes 4 and the sustain electrodes 5. A protective layer 7 is formed on the layer 6. A plurality of data electrodes 9 covered with an insulator layer 8 are provided on the back substrate 3, and a partition wall 10 is provided in parallel with the data electrodes 9 on the insulator layer 8 between the data electrodes 9. Yes. Further, the phosphors 11 are provided on the surface of the insulator layer 8 and the side surfaces of the partition walls 10 so that the scan electrodes 4 and the sustain electrodes 5 and the data electrodes 9 are orthogonal to each other. In the discharge space formed between the front substrate 2 and the back substrate 3, for example, a mixed gas of neon and xenon is enclosed as a discharge gas.
[0003]
FIG. 6 shows the electrode arrangement of this panel. N scan electrodes SCN1 to SCNn (scan electrode 4 in FIG. 5) and n sustain electrodes SUS1 to SUSn (sustain electrode 5 in FIG. 5) are alternately arranged in pairs in the row direction, and m in the column direction. The data electrodes D1 to Dm (data electrode 9 in FIG. 5) are arranged. A discharge cell 12 is formed at a portion where a pair of scan electrode SCNi and sustain electrode SUSi (i = 1 to n) and one data electrode Dj (j = 1 to m) intersect, and discharge cell 12 is discharged. M × n are formed in the space.
[0004]
Next, a driving method shown in Patent Document 1 for driving this panel will be described with reference to FIG.
[0005]
In FIG. 7, for example, one field period is composed of first to eighth subfields (SF1 to SF8) having an initialization period, a writing period, and a sustain period, whereby 256 gradation display is performed. Among these eight subfields, in seven subfields excluding SF1, the initialization operation in the initialization period is performed only in the discharge cells that are lit during the sustain period of the previous subfield. Yes.
[0006]
In the initialization period of SF1, all the data electrodes D1 to Dm and all the sustain electrodes SUS1 to SUSn are held at 0 (V), and the voltage Vp (below the discharge start voltage for all the scan electrodes SNC1 to SCNn). By applying a ramp voltage that gradually rises from V) toward the voltage Vr (V) exceeding the discharge start voltage, weak discharge occurs in all the discharge cells, and positive walls are formed on the sustain electrodes and the data electrodes. Charge is stored and negative wall charge is stored on the scan electrode. Thereafter, all the sustain electrodes SUS1 to SUSn are kept at the positive voltage Vh (V), and all the discharge cells are applied by applying a ramp voltage that gradually decreases toward Va (V) to all the scan electrodes SCN1 to SCNn. Causes a weak discharge to weaken the wall charge stored on each electrode. By such an initialization operation, the voltage in the discharge cell becomes close to the discharge start voltage.
[0007]
In the writing period of SF1, the display is performed by applying the scanning pulse voltage Vb (V) to the scanning electrode SCNi sequentially from the first row and simultaneously applying the writing pulse voltage Vw (V) to the data electrode Dj according to the video signal. Write discharge occurs only in the discharge cells to be performed. Thereby, wall charges corresponding to the video signal are formed in the discharge cells.
[0008]
In the sustain period of SF1, sustain pulse voltage Vm (V) is alternately applied to all scan electrodes SCN1 to SCNn and sustain electrodes SUS1 to SUSn, thereby causing a sustain discharge in the discharge cells that have caused the address discharge. A desired image display is performed by this sustain discharge.
[0009]
At the time when the initializing period of SF2 starts, in the discharge cell in which the sustain discharge is performed in SF1, positive wall charges exist on the sustain electrodes and the data electrodes, and negative wall charges exist on the scan electrodes. Yes. In the initialization period of SF2, all sustain electrodes are held at Vh (V), all data electrodes are held at 0 (V), and all scan electrodes are moved from Vm (V) to Va (V). Apply a slowly decreasing ramp voltage. While the lamp voltage is decreasing, a weak discharge is generated in the discharge cell that has undergone the sustain discharge in the immediately preceding sustain period (the sustain period of SF1), and the wall charges formed on each electrode are weakened, and the discharge cell Is close to the discharge start voltage. On the other hand, the discharge cells in which the address discharge and the sustain discharge are not performed in SF1 are not weakly discharged in the initialization period of SF2, and the wall charge state at the end of the initialization period of SF1 is maintained.
[0010]
For the writing period and sustain period of SF2, a sustain discharge is generated in the discharge cell corresponding to the video signal by applying the same waveform as in the case of SF1. For SF3 to SF8, a desired image display is performed by applying the same drive waveform as that of SF2 to each electrode.
[0011]
Thus, the initialization operation of SF1 is a complete initialization operation that discharges all discharge cells, and the initialization operation of SF2 to SF8 is a selection that causes discharge only in the discharge cells in which the sustain discharge has occurred in the immediately preceding sustain period. Initialization operation. Accordingly, light emission not related to gradation display is only the complete initialization operation of SF1, and furthermore, since the light emission is weak light emission accompanying the lamp waveform voltage, it is possible to display an image with high contrast.
[0012]
FIG. 8 shows a gradation display method of the plasma display. Since the plasma display uses the discharge phenomenon, the discharge cell 12 has only two states of lighting and non-lighting. Therefore, in order to perform halftone gradation expression, one field is divided into a plurality of subfields, each subfield is weighted according to the light emission luminance, and the presence or absence of light emission is controlled for each field. I am doing. For example, as shown in FIG. 8, one field is divided into eight subfields, and the emission luminance weights of SF1 to SF8 are “1”, “2”, “4”, “8”, “16”, Arrange as “32”, “64”, “128”. In the case of expressing the gradation “15”, the writing operation is performed in the writing period in SF1, SF2, SF3, and SF4, whereby “1”, “2”, “4”, and “8” that are the weights of the respective subfields. A sustain operation corresponding to is performed, and gradation “15” is expressed. In the case of expressing the gradation “16”, the sustain operation corresponding to the gradation “16” is performed by performing the writing operation only in SF5.
[0013]
For example, when SF1 is processed, among SF1 shown in FIG. 8, the discharge cell indicated by “1” is subjected to the write operation, and the discharge cell indicated by a blank is not subjected to the write operation. . In the sustain period, sustain pulses for sustaining are applied to the scan electrodes and sustain electrodes according to the values weighted in the respective subfields, and the same number of voltage pulses as the sustain pulses are applied to the data electrodes. A discharge cell displayed as “1” and subjected to an address operation is discharged with respect to each sustain pulse, and a predetermined luminance can be obtained with respect to a predetermined discharge cell by one discharge. In SF1, since the weight is “1”, a luminance of “1” level is obtained. In SF2, since the weight is “2”, a luminance level of “2” is obtained. As described above, the writing period is a period in which discharge cells that emit light are selected, and the sustain period is a period in which sustain light emission is performed a number of times corresponding to the weighting of each subfield.
[0014]
[Patent Document 1]
JP 2000-242224 A
[Problems to be solved by the invention]
However, in the above-described driving method, the discharge occurs just before the writing period only in the weak discharge in the initialization period of SF1 and the discharge of the sustain light emission of the number of times according to the weighting of each subfield in the sustain period. In such a driving method, for example, when the gradation “1” is expressed, the discharge occurs immediately before the writing period because the weak discharge in the initialization period of SF1 and the sustain period of SF1 as shown in FIG. Only one sustain emission is discharged. When discharge occurs, priming particles are generated in the discharge space, but the amount decreases as the discharge is weaker and the number of discharges is smaller. Further, as the amount of priming particles decreases, the time from the application of the write pulse until the first discharge occurs (discharge formation delay time) and the variation in the discharge start time of each pixel cell (discharge statistical delay time) increase. Therefore, for example, when the number of discharges is small immediately before the writing period as in the case where the gradation “1” is expressed, the writing discharge is caused by the writing pulse applied during the writing period because the amount of priming particles is small. There is a high possibility that it will not occur, and the cell is likely to be unlit.
[0016]
Moreover, after generation | occurrence | production, priming particle | grains reduce with time. For example, when expressing the gradation “16”, the discharge occurs immediately before the writing period of SF5 in which the writing operation must be performed, and the weak discharge in the initialization period of SF1 and the maintenance of SF5 as shown in FIG. It is only the discharge of sustain light emission for 16 periods. In this case, although the number of discharges of sustain light emission is as large as 16, the priming particles are decreased because the write period of SF5 is far from the initialization period of SF1 and the sustain light emission of SF5. In this manner, when the priming particles are decreased because the writing period in which the writing operation has to be performed is far from the initializing period of SF1 or the sustaining period in which sustaining light emission occurs, the writing pulse applied in the writing period is used. There is a high possibility that the writing discharge is not generated, and the cell tends to be unlit.
[0017]
The present invention has been made to solve the above-described problems, and by stabilizing the writing operation, cell non-lighting is suppressed and display characteristics are improved.
[0018]
[Means for Solving the Problems]
In order to solve the above-described problems, the plasma display panel driving method of the present invention provides a strong discharge initialization period before the writing period, and stabilizes the writing discharge by leaving more priming particles in the writing period. It is what makes you wake up.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 of the present invention is a driving method of a plasma display panel in which one field period is constituted by a plurality of subfields having a writing period and a sustain period, and at least of the plurality of subfields. A sustain period maintaining operation in one subfield and an initializing operation of the next subfield following the subfield are simultaneously performed, and a writing period in at least one subfield of the plurality of subfields A strong discharge initializing period is provided at the top of the head.
[0020]
According to a second aspect of the present invention, there is provided a driving method of a plasma display panel in which one field period is constituted by a plurality of subfields having a writing period and a sustain period, and at least one of the plurality of subfields. A sustain period maintaining operation in one subfield and an initializing operation of a next subfield following the subfield are simultaneously performed, and an initialization period is set in at least one subfield of the plurality of subfields And the initializing period is a strong discharge initializing period.
[0021]
Further, the invention according to claim 3 is characterized in that the strong discharge initialization period is provided in the initialization period of at least the first subfield among the plurality of subfields, and the invention according to claim 4 is characterized in that The strong discharge initialization period is to apply a voltage waveform having a voltage change rate of 5 V / μs or more, and the invention according to claim 5 is characterized in that the strong discharge initialization period has a rectangular waveform. A voltage is applied.
[0022]
Hereinafter, a method for driving a plasma display panel according to an embodiment of the present invention will be described with reference to FIGS.
[0023]
FIG. 1 is an operation timing chart in the driving method according to the embodiment of the present invention. Here, a description will be given assuming that one field period is composed of eight subfields (SF1 to SF8) having an initialization period, a writing period, and a sustain period. As shown in FIG. 1, one field period is composed of eight subfields having an initialization period, a writing period, and a sustain period. In SF1, the initialization period is provided independently. In the other SF2 to SF8, the initialization operation in the initialization period is configured to be performed simultaneously with the final maintenance operation A in the maintenance period of the previous subfield. In FIG. 1, except for the initialization period of SF1, the operation from the beginning of SF1 to the end of SF8 from the beginning of SF2 to the end of SF2 is the same as the operation described in the conventional example.
[0024]
As shown in FIG. 1, in the initialization period of SF1, all data electrodes D1 to Dm and all sustain electrodes SUS1 to SUSn are held at 0 (V), and all scan electrodes SCN1 to SCNn are discharged. By applying a rectangular waveform voltage P1 having a voltage Vr (V) exceeding the start voltage, a strong discharge is caused in all the discharge cells, and a large amount of priming particles are generated in the cells. Further, positive wall charges are stored on the sustain electrodes and the data electrodes, and negative wall charges are stored on the scan electrodes. Thereafter, all the sustain electrodes SUS1 to SUSn are maintained at the positive voltage Vh (V), and all the discharges are applied by applying the ramp voltage R that gradually decreases toward Va (V) to all the scan electrodes SCN1 to SCNn. By causing a weak discharge in the cell and weakening the wall charges stored on each electrode, the voltage in the discharge cell becomes close to the discharge start voltage. The period during which such an initialization operation involving strong discharge is performed is called a strong discharge initialization period. In the present invention, this strong discharge initialization period is provided at the head of SF1.
[0025]
Therefore, for example, when expressing the gradation “1”, the discharge occurs just before the writing period only once during the sustain period of SF1, but a strong discharge occurs during the initialization period of SF1. By shifting to the strong discharge initialization period, a large amount of priming particles generated by the strong discharge remain in the discharge cell when the next writing period starts, and from the application of the writing pulse until the first discharge occurs. Variation in time (discharge formation delay time) and discharge start time of each pixel cell (discharge statistical delay time) is reduced. Thereby, the writing discharge in the writing period is stably caused, so that the occurrence of non-lighting can be avoided and the display characteristics can be improved.
[0026]
At this time, all the data electrodes D1 to Dm and all the sustain electrodes SUS1 to SUSn are held at 0 (V) during the conventional initialization period, and are equal to or lower than the discharge start voltage for all the scan electrodes SCN1 to SCNn. By applying a ramp voltage that gradually rises from the voltage Vp (V) toward the voltage Vr (V) exceeding the discharge start voltage, a weak discharge is caused in all the discharge cells, and the sustain electrode and the data electrode are formed. In this method, positive wall charges are stored and negative wall charges are stored on the scan electrodes. In the present invention, a rectangular waveform voltage exceeding the discharge start voltage is applied instantaneously without using the slowly rising ramp voltage. As a result, the time required for the initialization period can be shortened as compared with the prior art. Therefore, this is a particularly effective driving method for a high definition panel whose driving time increases.
[0027]
In the above embodiment, the case where the strong discharge initialization period is included in the initialization period of the first SF1 is shown. However, the present invention is not limited to this, and the initialization period in at least one subfield among a plurality of subfields is used. The same effect can be obtained even when the strong discharge initialization period is included. Furthermore, in the above-described embodiment, an example in which the rectangular waveform voltage P1 is applied between the strong discharge initialization groups has been described. However, the present invention is not limited to this, and the strong discharge initialization period is 5 V / μs or more as shown in FIG. A similar effect can be obtained even when a rectangular waveform voltage P2 having a voltage change rate is applied.
[0028]
Next, another embodiment of the present invention will be described with reference to a drive waveform timing chart shown in FIG. In the above embodiment, the case where the strong discharge initialization period is provided in the initialization period of SF1 has been described. However, in the embodiment shown in FIG. 3, the strong discharge is performed in the initialization period of SF1 and the initialization period of SF5. An initialization period is provided. The operation in the strong discharge initialization period according to this embodiment is the same as that in the above embodiment. However, in this embodiment, for example, when expressing gradation “16”, Immediately before the discharge occurs, the strong discharge in the strong discharge initialization period of SF1 and the strong discharge in the strong discharge initialization period of SF5 and 16 sustain light emission in the sustain period.
[0029]
In this case, the writing period of SF5 in which the writing operation must be performed in the conventional driving method is that the priming particles are reduced because it is far in time from the initialization period of SF1 and the sustain light emission of SF5, but the initialization period of SF5 Due to the strong discharge, a large amount of priming particles generated during the initialization period of SF5 remain in the discharge cell even in the subsequent SF5 writing period, and the time from the application of the writing pulse until the first discharge occurs. (Discharge formation delay time) and variations in discharge start time of each pixel cell (discharge statistical delay time) are reduced. Therefore, the writing discharge in the writing period can be stably caused, and the display characteristics can be improved by avoiding the non-lighting.
[0030]
In this embodiment, the case where the strong discharge initializing period is included in the initializing periods SF1 and SF5 has been described. However, the present invention is not limited to this, and at least SF1 is included in a plurality of subfields included in one field period. The same effect can be obtained even if a strong discharge initialization period is included in any of the initialization periods of the included subfield group. Further, in the embodiment of FIG. 3, the example in which the strong discharge initialization period applies the rectangular waveform voltage P1 is shown, but as in the embodiment shown in FIGS. 1 and 2, as shown in FIG. The same effect can be obtained even when a rectangular wave voltage P2 having a voltage change rate of 5 V / μs or more in the strong discharge initialization period is applied.
[0031]
【The invention's effect】
As is clear from the above description, according to the driving method of the plasma display panel of the present invention, the write discharge is performed by providing a strong discharge initialization period before the write period and leaving more priming particles in the write period. Can be stably caused, and the display characteristics can be improved by suppressing the non-lighting of the cell. Furthermore, since the ramp waveform voltage that gradually rises in the conventional initialization period is changed to a rectangular waveform voltage that rises sharply in the present invention, the time required for the initialization period can be shortened compared to the conventional case. In particular, this is an effective driving method for a high-definition panel whose driving time increases.
[Brief description of the drawings]
FIG. 1 is an operation drive timing diagram showing a method for driving a plasma display panel according to an embodiment of the present invention. FIG. 2 is an operation drive timing diagram showing an example in which a voltage waveform is changed in the embodiment shown in FIG. 3 is an operation drive timing diagram showing a method of driving a plasma display panel according to another embodiment of the present invention. FIG. 4 is an operation drive timing diagram showing an example in which the voltage waveform is changed in the embodiment shown in FIG. 5 is a perspective view showing a conventional plasma display panel. FIG. 6 is an electrode arrangement diagram of the plasma display panel. FIG. 7 is an operation drive timing chart showing a driving method of the conventional plasma display panel. Explanatory drawing showing key expression method [Explanation of symbols]
P1, P2 rectangular waveform voltage

Claims (5)

A driving method of a plasma display panel in which one field period is constituted by a plurality of subfields having a writing period and a sustaining period, and a sustaining period sustaining operation in at least one subfield among the plurality of subfields; An initialization operation for the next subfield following the subfield is performed simultaneously, and a strong discharge initialization period is provided at the beginning of the write period in at least one subfield of the plurality of subfields. A method for driving a plasma display panel. A driving method of a plasma display panel in which one field period is constituted by a plurality of subfields having a writing period and a sustaining period, and a sustaining period sustaining operation in at least one subfield among the plurality of subfields; An initializing operation of the next subfield following the subfield is performed at the same time, and an initializing period is provided in at least one subfield of the plurality of subfields, and the initializing period is set as an initial strong discharge. A method for driving a plasma display panel, characterized in that a period of time is set. 3. The method of driving a plasma display panel according to claim 2, wherein the strong discharge initializing period is provided in an initializing period of at least the first subfield among the plurality of subfields. 3. The method for driving a plasma display panel according to claim 1, wherein a voltage waveform having a voltage change rate of 5 V / [mu] s or more is applied during a strong discharge initialization period. 3. The method of driving a plasma display panel according to claim 1, wherein the strong discharge initializing period applies a voltage having a driving waveform.

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