JP2010145905A - Method for driving plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for driving a plasma display panel (PDP), which can suppress burning. <P>SOLUTION: In a three-electrode plasma display panel, a front substrate on which scanning electrodes and sustain electrodes are formed and a rear substrate on which data electrodes are formed are arranged opposite to each other. When burning occurs due to the stillness of the same image for a fixed period in the plasma display panel, the driving method drives the plasma display panel so that the recovery time of a sustain pulse voltage is sharpened (16a→16b) for the fixed period, and/or the sustain pulse voltage is increased for the fixed period. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for driving a plasma display panel.

  A plasma display panel (hereinafter abbreviated as PDP) generally includes a front substrate in which n scan electrodes SCN1 to SCNn and n sustain electrodes SUS1 to SUSn are arranged in pairs, and m data electrodes D1 to D1. The rear substrate on which Dm is arranged is arranged to face each other across the discharge space. Therefore, a large number of discharge cells (one m × in this case) are included in the discharge space including one pair of scan electrode SCNi-sustain electrode SUSi pair (i = 1 to n) and one data electrode Dj (j = 1 to m). n) are formed.

In addition, an image display device using a PDP divides one field period of a video signal into a plurality of subfields having luminance weights (luminance weights), and uses the discharge cells as the number of times corresponding to the luminance weights in each subfield. Causes a discharge. A driving method for expressing the gradation of a video signal by combining subfields that cause discharge is used. Among them, a driving method (high contrast driving) for reducing the number of times of light emission not related to gradation expression as much as possible and improving the contrast ratio has been proposed (see, for example, Patent Document 1).
JP 2000-242224 A

  In the PDP panel, there is a problem that when the same image is displayed stationary for a certain period of time, the image becomes a so-called burn-in.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a PDP driving method capable of suppressing burn-in.

  In order to achieve the above object, the PDP driving method of the present invention uses the same image for a certain time in a three-electrode plasma display panel in which a front substrate on which scan electrodes and sustain electrodes are formed and a rear substrate on which data electrodes are formed are arranged to face each other. When burn-in occurs due to the stationary state, the recovery time of the sustain pulse voltage is made steep for a certain period of time.

  In order to achieve the above object, the PDP driving method according to the present invention is applied to a three-electrode plasma display panel in which a front substrate on which scan electrodes and sustain electrodes are formed and a rear substrate on which data electrodes are formed are opposed to each other for a certain period of time. In the case where burn-in occurs due to the same image being stationary, the sustain pulse voltage is increased for a certain period of time.

  According to the present invention, it is possible to provide a method for driving a PDP that can suppress burn-in.

  Hereinafter, a PDP driving method according to an embodiment of the present invention will be described with reference to the drawings. However, the embodiment of the present invention is not limited thereto.

  FIG. 1 is an exploded perspective view showing a schematic configuration of a PDP driven by a PDP driving method according to an embodiment of the present invention.

  The PDP 1 includes a front substrate 2 and a rear substrate 3 that are arranged to face each other. The front substrate 2 has a plurality of pairs of scan electrodes 5 and sustain electrodes 6 formed on a front glass plate 4 in parallel with each other. A dielectric layer 7 is formed so as to cover the scan electrodes 5 and the sustain electrodes 6, and a protective layer 8 is formed so as to cover the surface of the dielectric layer 7. In the rear substrate 3, a plurality of data electrodes 10 are formed in parallel to each other on a rear glass plate 9, and a dielectric layer 11 is formed so as to cover the data electrodes 10. A plurality of barrier ribs 12 are formed on the dielectric layer 11 in parallel with the data electrodes 10, and a phosphor layer 13 is formed on the surface of the dielectric layer 11 and the side surfaces of the barrier ribs 12. Further, a discharge gas is sealed in the discharge space 14 sandwiched between the front substrate 2 and the rear substrate 3.

  FIG. 2 is a diagram schematically showing an electrode arrangement of the PDP 1.

  M columns of data electrodes D1 to Dm (data electrode 10 in FIG. 1) are arranged in the column direction, and n rows of scan electrodes SCN1 to SCNn (scan electrode 5 in FIG. 1) and n rows of sustain electrodes SUS1 are arranged in the row direction. SUSn (sustain electrodes 6 in FIG. 1) are alternately arranged. Then, m × n discharge cells 15 including a pair of scan electrodes SCNi, sustain electrodes SUSi (i = 1 to n) and one data electrode Dj (j = 1 to m) are formed in the discharge space. Yes.

  Next, drive waveforms and timings in the PDP drive method according to the embodiment of the present invention will be described. In the present embodiment, one field period is described as being composed of first to eighth subfields having an initialization period, a writing period, and a sustain period. It may be a configuration.

  FIG. 3 is a diagram schematically showing a driving waveform in the driving method of the PDP according to the embodiment of the present invention.

  In the first half of the initializing period of the first subfield, all the data electrodes D1 to Dm and all the sustain electrodes SUS1 to SUSn are held at 0 (V), and all the sustain electrodes are included in all the scan electrodes SCN1 to SCNn. A ramp waveform voltage that gently rises from a voltage Vp (V) that is equal to or lower than the discharge start voltage to a voltage Vr (V) that exceeds the discharge start voltage is applied as a first upward ramp waveform voltage to SUS1 to SUSn. While this ramp voltage rises, in each discharge cell 15, the first weak initializing discharge is applied from all the scan electrodes SCN1 to SCNn to all the sustain electrodes SUS1 to SUSn and all the data electrodes D1 to Dm. As a result, negative wall voltage is accumulated on scan electrodes SCN1 to SCNn, and positive wall voltage is accumulated on all data electrodes D1 to Dm and all sustain electrodes SUS1 to SUSn.

  In the latter half of the initializing period of the first subfield, all sustain electrodes SUS1 to SUSn are kept at positive voltage Ve (V), and all scan electrodes SCN1 to SCNn are discharged to all sustain electrodes SUS1 to SUSn. A ramp waveform voltage that gently falls from a voltage Vq (V) that is equal to or lower than the start voltage to a voltage Va ′ (V) that exceeds the discharge start voltage is applied. While this ramp voltage falls, the second weak initializing discharge occurs again from all the sustain electrodes SUS1 to SUSn to all the scan electrodes SCN1 to SCNn in all the discharge cells 15, and all the scan electrodes SCN1. The negative wall voltage above SCNn and the positive wall voltage above all sustain electrodes SUS1 to SUSn are weakened. Further, a weak discharge occurs between all the data electrodes D1 to Dm and all the scan electrodes SCN1 to SCNn, and the positive wall voltage above all the data electrodes D1 to Dm is adjusted to a value suitable for the write operation. Is done. Thus, the complete initialization operation for forcibly discharging all the discharge cells is completed.

  In the writing period of the first subfield, all the scan electrodes SCN1 to SCNn are temporarily held at Vscan (V), and among the data electrodes D1 to Dm, the data electrode Dk (corresponding to the discharge cell 15 to be displayed in the first row is displayed. k represents an integer of 1 to m), and a positive write pulse voltage Vdata (V) is applied to the scan electrode SCN1 in the first row, and a scan pulse voltage Va (V) is applied to the scan electrode SCN1 in the first row. At this time, the voltage difference at the intersection between the upper portion of the data electrode Dk to which the positive write pulse voltage Vdata (V) is applied and the upper portion of the scan electrode SCN1 is positive with respect to the write pulse voltage Vdata (V) above the data electrodes D1 to Dm. Since the wall voltage is added and exceeds the discharge start voltage, an address discharge occurs between the sustain electrode SUS1 and the scan electrode SCN1 and between the data electrode Dk and the scan electrode SCN1 at this intersection. A positive voltage is accumulated on the upper part of the scan electrode SCN1, a negative voltage is accumulated on the sustain electrode SUS1, and a negative voltage is accumulated on the data electrode Dk where the write discharge has occurred. On the other hand, the voltage difference at the intersection between the upper portion of the data electrode Dl (l represents an integer of 1 to m) and the upper portion of the scan electrode SCN1 to which the positive write pulse voltage Vdata (V) is not applied does not exceed the discharge start voltage. Therefore, no write discharge occurs.

  A similar write operation is performed until the discharge cell in the n-th row, and the write operation is completed.

  In the sustain period of the first subfield, first, all scan electrodes SCN1 to SCNn and sustain electrodes SUS1 to SUSn are once returned to 0 (V), and then positive sustain pulse voltage Vss is applied to all scan electrodes SCN1 to SCNn. Apply (V). At this time, the voltage between the upper part of scan electrode SCNi and the upper part of sustain electrode SUSi in discharge cell 15 in which the write discharge has occurred is the positive wall voltage accumulated on upper part of scan electrode SCNi and the upper part of sustain electrode SUSi in the write period. The accumulated negative wall voltage is added to the sustain pulse voltage Vss (V), which exceeds the discharge start voltage. Therefore, a sustain discharge occurs between scan electrode SCNi and sustain electrode SUSi in the discharge cell in which the write discharge has occurred, and a negative wall voltage is accumulated above scan electrode SCNi in the discharge cell in which this sustain discharge has occurred. A positive wall voltage is accumulated on the sustain electrode SUSi. Subsequently, when all the scan electrodes SCN1 to SCNn are returned to 0 (V) and a positive sustain pulse voltage Vss (V) is applied to all the sustain electrodes SUS1 to SUSn, the sustain electrode SUSi in the discharge cell in which the sustain discharge has occurred. The voltage between the upper part and the upper part of scan electrode SCNi again exceeds the discharge start voltage, and a sustain discharge occurs between sustain electrode SUSi and scan electrode SCNi. Similarly, the positive sustain pulse voltage Vss (V) is alternately applied to all the scan electrodes SCN1 to SCNn and all the sustain electrodes SUS1 to SUSn, so that the discharge cell 15 that has caused the address discharge is sub- The sustain discharge is continued for the number of times corresponding to the weighting of the luminance of the field.

  On the other hand, since the wall voltage of the upper part of scan electrode SCNi and the upper part of sustain electrode SUSi in the discharge cell in which no write discharge has occurred remains weakened in the latter half of the initializing period of the first subfield, scanning is performed even when the sustain voltage is applied. The discharge start voltage is not exceeded between the upper part of the electrode SCNi and the upper part of the sustain electrode SUSi. For this reason, no sustain discharge occurs in the discharge cells that did not cause the write discharge.

  In the second half of the initialization period of the second to eighth subfields, all the sustain electrodes SUS1 to SUSn are kept at the positive voltage Ve (V), and all the scan electrodes SCN1 to SCNn are changed from 0 (V) to Va ′ ( A ramp waveform voltage that gradually falls toward V) is applied. At this time, in the discharge cell in which the sustain discharge has occurred, the second weak initializing discharge occurs from the sustain electrode SUSi to the scan electrode SCNi, and the negative wall voltage above the scan electrode SCNi and the positive wall voltage above the sustain electrode SUSi. Is weakened. Further, a weak discharge occurs between the data electrode Dk and the scan electrode SCNi, and the positive wall voltage on the electrode Dk is adjusted to a value suitable for the write operation.

  On the other hand, in the discharge cells that have not caused the sustain discharge, the discharge between scan electrode SCNi and sustain electrode SUSi does not occur. Further, no discharge occurs between scan electrode SCNi and data electrode Dl.

  In addition, among the discharge cells in which no sustain discharge has occurred, the discharge cells in which the positive wall voltage above the data electrode Dl ′ is insufficient due to the influence of the write discharge or the sustain discharge of the adjacent discharge cells are scanned. No discharge occurs between the electrode SCNi and the sustain electrode SUSi. However, a weak discharge occurs between the data electrode Dl ′ and the scan electrode SCNi, and the positive wall voltage on the electrode Dl ′ is adjusted to a value suitable for the write operation.

  As described above, (1) a discharge cell in which a sustain discharge has occurred, (2) a discharge cell in which no sustain discharge has occurred, and (3) an address discharge or sustain in an adjacent discharge cell among the discharge cells in which a sustain discharge has not occurred. In any discharge cell in which the positive wall voltage above the data electrode is insufficient due to the influence of the discharge, the wall voltage above each of the scan electrode, the sustain electrode, and the data electrode is the first. It becomes equal to the wall voltage at the end of the complete initialization operation in the subfield.

  The writing period and sustain period in the second to eighth subfields are the same as the operation in the first subfield, and thus description thereof is omitted. In the PDP driving method of the present embodiment, the complete initialization operation is performed in the initialization period of the first subfield. However, the complete initialization operation is performed in the initialization period of any other subfield. Alternatively, it may be performed once every plural fields (for example, once every two fields).

  FIG. 4 is a block diagram showing a schematic configuration of a plasma display device 50 that performs a method of driving a PDP according to an embodiment of the present invention. The plasma display device 50 includes a PDP 1 for displaying an image and a driving device 100 for selectively lighting the discharge cells of the PDP 1 in accordance with the image signal.

  The driving device 100 includes a video signal processing circuit 101, a data electrode driving circuit 102, a timing control circuit 103, a scanning electrode driving circuit 104, and a sustain electrode driving circuit 105. The video signal and the synchronization signal are input to the video signal processing circuit 101. The video signal processing circuit 101 outputs a subfield signal for controlling whether or not each subfield is lit to the data electrode driving circuit 102 based on the video signal and the synchronization signal. The synchronization signal is also input to the timing control circuit 103. The timing control circuit 103 outputs a timing control signal to the data electrode driving circuit 102, the scan electrode driving circuit 104, and the sustain electrode driving circuit 105 based on the synchronization signal.

  The data electrode drive circuit 102 applies a pulse to the data electrode 10 (data electrodes D1 to Dm in FIG. 2) according to the subfield signal and the timing control signal. Scan electrode drive circuit 104 applies a pulse to scan electrode 5 (scan electrodes SCN1 to SCNn in FIG. 2) in response to the timing control signal, and sustain electrode drive circuit 105 in response to the timing control signal, sustain electrode 6 (FIG. 2 SUS1 to SUSn). Necessary power is supplied from the power supply circuit to the data electrode drive circuit 102, the scan electrode drive circuit 104, and the sustain electrode drive circuit 105.

  Here, the burn-in occurs because the difference in the discharge start voltage between the discharge cells that are lit and the discharge cells that are not lit increases when the image is stationary for a certain period of time. Therefore, in order to suppress the occurrence of burn-in, it is effective to make the discharge timings of the lit discharge cells and the non-lighting discharge cells uniform by increasing the sustain pulse voltage or by sharpening the recovery time of the sustain pulse voltage. is there.

  Therefore, in the PDP driving method according to the embodiment of the present invention, the video signal processing circuit 101 detects the same video signal for a certain period of time as an index for occurrence of burn-in. In such a case, As schematically shown in the waveform of FIG. 5, by making the recovery time of the sustain pulse voltage steep (16a → 16b), the discharge timings of the lit discharge cells and the non-lighted discharge cells are aligned, so that the burn-in occurs. It is possible to disappear quickly.

  Here, FIG. 5A shows a normal waveform, and FIG. 5B shows a sharp recovery time of the sustain pulse voltage when the video signal processing circuit 101 detects the same video signal for a certain period of time. The waveform at the time of carrying out is shown typically, 16a and 16b show the collection time in each.

  In the PDP driving method according to the embodiment of the present invention, when the video signal processing circuit 101 detects the same video signal for a certain period of time, the sustain pulse is schematically shown in FIG. By increasing the voltage (17a → 17b), the discharge timings of the lit discharge cells and the non-lighting discharge cells are aligned, thereby making it possible to quickly eliminate the burn-in.

  Here, FIG. 6A shows a normal waveform, and FIG. 6B shows a waveform when the sustain pulse voltage is increased when the video signal processing circuit 101 detects the same video signal for a certain period of time. 16a is a recovery time in each, and 17a and 17b are sustain pulse voltages in each.

  In the case shown in FIG. 6, similar to the case shown in FIG. 5, when the video signal processing circuit 101 detects the same video signal for a certain period of time, an operation of making the recovery time 16 a steep may be combined.

  In the above description, the image signal processing circuit 101 detects the same video signal for a certain period of time as an index for occurrence of burn-in. However, the present invention is not limited to this, and burn-in occurs. Any other method may be used as long as the method is recognized.

  As described above, the present invention is useful for providing a large-screen, high-definition plasma display panel.

1 is an exploded perspective view showing a schematic configuration of a PDP driven by a PDP driving method according to an embodiment of the present invention. The figure which shows typically the electrode arrangement | sequence of PDP driven by the driving method of PDP by one embodiment of this invention The figure which shows schematically the drive waveform in the drive method of PDP by one embodiment of this invention. The block diagram which shows schematic structure of the plasma display apparatus which performs the drive method of PDP by one embodiment of this invention The figure which shows typically the drive waveform in the drive method of PDP by one embodiment of this invention. The figure which shows typically the drive waveform in the drive method of PDP by one embodiment of this invention.

Explanation of symbols

1 PDP
2 Front substrate 3 Rear substrate 4 Front glass plate 5 Scan electrode 6 Sustain electrode 7 Dielectric layer 8 Protective layer 9 Back glass plate 10 Data electrode 11 Dielectric layer 12 Partition wall 13 Phosphor layer 14 Discharge space 15 Discharge cells 16a and 16b Maintain Pulse voltage recovery time 17a, 17b Sustain pulse voltage 50 Plasma display device 100 Drive device 101 Video signal processing circuit 102 Data electrode drive circuit 103 Timing control circuit 104 Scan electrode drive circuit 105 Sustain electrode drive circuit

Claims (2)

In a three-electrode plasma display panel in which a front substrate on which scan electrodes and sustain electrodes are formed and a rear substrate on which data electrodes are formed are opposed to each other, if the same image is stationary for a certain period of time, A method for driving a plasma display panel, characterized in that the recovery time of the sustain pulse voltage is made steep. In a three-electrode plasma display panel in which a front substrate on which scan electrodes and sustain electrodes are formed and a rear substrate on which data electrodes are formed are opposed to each other, if the same image is stationary for a certain period of time, A method for driving a plasma display panel, wherein the sustain pulse voltage is increased during the period.

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