JP4273713B2 - Driving method of plasma display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a driving method of a plasma display panel used as a television or a monitor.
[0002]
[Prior art]
  FIG. 7 shows a perspective view of an AC surface discharge type plasma display panel (hereinafter referred to as a panel), and FIG. 8 shows an electrode structure. As shown in FIG. 7, in the panel 1, the front glass side substrate 2 and the back side glass second substrate 3 are arranged to face each other, and a discharge occurs in the gap. A gas that emits ultraviolet light, such as neon and xenon, is enclosed in the container.
[0003]
  On the first substrate 2, an electrode group consisting of a pair of strip-like scan electrodes 4 and sustain electrodes 5 covered with the first dielectric layer 6 and the protective film 7 is arranged in parallel in the row direction. Yes.
[0004]
  On the second substrate 3, strip-like write electrodes 11 covered with the second dielectric layer 10 are arranged in parallel with each other in the column direction orthogonal to the scan electrodes 4 and the sustain electrodes 5. In addition, strip-shaped barrier ribs 8 are provided between the write electrodes 11 in order to isolate the write electrodes 11 and form a discharge space. Further, a phosphor layer 9 is applied from the second dielectric layer 10 to the side surface of the partition wall 8.
[0005]
  The panel 1 is configured to see an image display from the first substrate 2 side, and the phosphor layer 9 is excited by ultraviolet rays generated by a discharge between the scan electrode 4 and the sustain electrode 5 in the discharge space. The visible light from the phosphor layer 9 is used for display light emission.
[0006]
  As shown in FIG. 8, each of the scanning electrode 4 and the sustaining electrode 5 is composed of metal bus bars 4A and 5A and transparent electrodes 4B and 5B for increasing conductivity. The transparent electrodes 4B and 5B have a function of spreading the discharge so that the discharge occurs with a larger volume.
[0007]
  Next, a conventional driving method will be described with reference to FIGS.
[0008]
  In the conventional panel driving method, one field is divided into a plurality of subfields as shown in FIG. The brightness that can be displayed is different in each subfield, and gradation display is performed by a combination of these subfields. Each subfield includes an initialization period, a writing period, and a sustain period, and the brightness displayed in the subfield varies depending on the length of the sustain period.
[0009]
  In FIG.OneIn the sub-field, an example of a voltage waveform applied to each of the scan electrode 4, the sustain electrode 5, and the write electrode 11 and discharge light emission by the voltage waveform are shown. 10A shows examples of voltage waveforms applied to the scan electrode 4, FIG. 10B shows sustain electrodes 5, and FIG. 10C shows examples of voltage waveforms applied to the write electrodes 11, respectively. FIG. 10D schematically shows the intensity of discharge light emission caused by this drive voltage waveform.
[0010]
  In FIG. 10, first, the initialization pulse Vset is applied to the scan electrode 4 to initialize the charge state in the discharge cell of the panel, and then the voltage Ve is applied to the sustain electrode 5 so that the potential of the scan electrode 4 is gradually reduced. By changing to Va, the charges accumulated in the first dielectric layer 6 and the phosphor layer 9 are adjusted for the subsequent writing period. Next, the bias voltage Vscan is applied to the scanning electrodes 4 other than the cell to be selected, the bias voltage Vscan is removed from the selected cell, and at the same time, the write pulse Vd is applied to the write electrode 11 to cause write discharge.
[0011]
  By this writing discharge, charges are accumulated on the surfaces of the first dielectric layer 6, the protective film 7 and the phosphor layer 9. A similar write operation is sequentially performed over the entire panel to select cells to be displayed.
[0012]
  Next, in order to perform the sustain discharge, the write electrode 11 is grounded, and the sustain pulse Vs is alternately applied to the scan electrode 4 and the sustain electrode 5, whereby the first dielectric layer is formed in the cell in which the wall charges are accumulated. When the potential of the surface 6 exceeds the discharge start voltage, a discharge is generated, and the sustain discharge is repeatedly performed during the period (sustain period) in which the sustain pulse Vs is applied. The charges accumulated in the first dielectric layer 6 and the phosphor layer 9 are called wall charges and play an important role in driving the panel.
[0013]
  The movement of wall charges in the conventional driving method will be described in detail with reference to FIG. FIG.OneFIG. 11 is a cross-sectional view of the discharge cell taken along the write electrode 11. For the sake of simplicity, the scan electrode 4, the sustain electrode 5, the first dielectric layer 6, and the phosphor layer 9 are shown in FIG. , Only the write electrode 11 is schematically shown. In addition, voltages applied to the respective electrodes are drawn from the electrodes.
[0014]
  FIGS. 11B to 11G correspond to times t1 to t6 in FIG. 10, respectively. The discharge in the initialization period is intended to adjust the wall charge so that the write discharge as the selection operation normally occurs in the subsequent write period.
[0015]
  In the first initialization period (time t 1), which is the first initialization step, a positive voltage Vset is applied to the scan electrode 4 to generate a discharge between the scan electrode 4, the sustain electrode 5, and the write electrode 11. Due to this discharge, negative wall charges are accumulated in the first dielectric layer 6 on the scan electrode 4, and positive wall charges are accumulated in the first dielectric layer 6 on the sustain electrode 5 and the write electrode 11. (FIG. 11 (b)).
[0016]
  In the second initialization period (time t2), which is the subsequent second initialization step, the positive voltage Ve is applied to the sustain electrode 5 and the potential applied to the scan electrode 4 is gradually lowered. When the potential obtained by superimposing the wall charges accumulated in the first initialization period on the potential difference between scan electrode 4 and sustain electrode 5 exceeds the discharge start voltage, discharge occurs between scan electrode 4 and sustain electrode 5. Start. At this time, since the change in the voltage applied to the scan electrode 4 is gradual, the movement of the wall charge due to the discharge becomes gradual, and the charge is moved while the discharge space is kept close to the discharge start voltage.
[0017]
  Therefore, at the end of the initialization period (first initialization period + second initialization period) (time t3), the scan electrode 4 and the sustain electrode 5 are close to the discharge start voltage in a state close to the scan electrode. Thus, positive wall charges are accumulated in 4 and negative wall charges are accumulated in the sustain electrode 5 (FIG. 11D). Such an initialization method is a driving method described in Japanese Patent Publication No. 2000-501199. It is possible to suppress light emission due to initialization discharge weakly by adjusting wall charges by weak discharge, and to start discharge of the cell. This is an excellent driving method in that the wall charge is automatically adjusted according to the voltage.
[0018]
  After such an initialization period, immediately before the writing period, which is the writing step, negative wall charges are accumulated on the scanning electrode 4 and positive wall charges are accumulated on the sustain electrode 5 and the writing electrode 11. By applying a positive write pulse to the write electrode 11, write discharge can be performed (FIG. 11E). By this writing discharge, wall charges are arranged between the scan electrode 4 and the sustain electrode 5 so as to cancel out the potential difference applied from the outside, and the positive wall charge is placed on the scan electrode 4 and the wall charge is placed on the sustain electrode 5. Can be accumulated (FIG. 11 (f)).
[0019]
  In this state, during the sustain period (time t6), which is a sustain step, a positive voltage is applied to scan electrode 4 and a negative voltage (or ground potential) is applied to sustain electrode 5, thereby accumulating accumulated wall charges. Sustain discharge starts due to the effect of superimposing the electric potential and the external voltage. In a discharge cell in which no write discharge is performed, the arrangement of wall charges remains in the state shown in FIG. 11 (d). There is not enough sustain discharge. This is the principle of the selection operation in the panel. The initialization period (first initialization period + second initialization period), writing period, and sustain period are repeated in each of these subfields.
[0020]
  At this time, the discharge cell once lit is lit even if there is no initialization period, but the wall charge of the discharge cell waiting without being lit has changed when lit from the complete initial state. Even in this case, one initialization period is provided in this one field in order to restore the normal state.
[0021]
[Problems to be solved by the invention]
  In the conventional driving method described above, there is a problem in that charge movement different from the original is performed during the writing period. As a result, charge transfer due to discharge reaches adjacent discharge cells. This is presumed to be due to the following phenomenon.
[0022]
  That is, since the discharge in the writing period is performed sequentially for each row, the cells in the row adjacent to the discharging cells are not originally discharged, but in the discharging cells. It becomes a situation where charged particles are likely to flow by the writing discharge. As a result, write discharge occurs in cells that are not originally written discharge, which is called crosstalk, and the wall charge that should be originally lost is lost due to the movement of charged particles, or excess wall charge is accumulated, resulting in defective lighting. As a result, the display quality was lowered.
[0023]
  In the future, when the pitch of cells in adjacent rows is reduced by changing the electrode dimensions in order to increase the definition, such a crosstalk phenomenon will become a big problem. In addition, there is a problem that the contrast is lowered to cause a strong discharge in order to return the wall charge to a normal state in the initialization period for each subfield.
[0024]
  The present invention is intended to solve the problems of such a conventional configuration, and can prevent abnormal discharge such as crosstalk by a simple method and improve a stable and high-quality image. The purpose is to obtain the indication.
[0025]
[Means for Solving the Problems]
  In order to solve the above-described problems, the present invention provides a first substrate on which a scan electrode and a sustain electrode that are opposed to each other are formed by forming a discharge gap, and the scan electrode and the sustain electrode that are disposed so as to face the first substrate. A second substrate on which write electrodes are formed in a direction perpendicular to each other, and each of the scan electrode and the sustain electrode includes a discharge start portion that is a portion near the discharge gap and a discharge end portion that is a portion far from the discharge gap. A driving method of a formed plasma display panel, wherein one field is constituted by a plurality of subfields, and the subfield includes an initialization step including a first initialization step and a second initialization step, and the initialization Select discharge cells provided after the step and displaying by applying voltage to the scan and write electrodes And a sustain step in which a sustain discharge is generated in the discharge cells selected in the write step and display is performed. In the first initialization step, a negative first direction is applied to the scan electrode. In addition to applying a potential voltage and applying a positive second potential voltage to the sustain electrode, a discharge is generated in both the discharge start portion and the discharge end portion, and then in the second initialization step, From the first potential to the positive third potential on the scan electrodeVoltage that changes more slowly than during the first initialization stepTo the sustain electrode from the second potential toward a fourth potential lower than the second potential.Voltage that changes more slowly than during the first initialization stepIn the write step, a negative voltage is applied to the scan electrode for writing and a positive voltage is applied to the write electrode in the write step. Between the write electrode and the discharge start portion of the scan electrodeDischargeAnd generating a discharge between the discharge start portions of the scan electrode and the sustain electrode, and at least one subfield of the plurality of subfields is in the last subfield sustain step.For the last pulse, by applying a voltage so that wall charges of the same polarity as during the discharge of the first initialization step are accumulated,In the first initialization step, a portion where a negative first potential is applied to the scan electrode is omitted.
[0026]
  According to the present invention,By generating discharge only at the discharge start part at the time of writing, preventing abnormal discharge such as crosstalk, preventing strong discharge for each subfield, weakening the intensity of light emission independent of display, A stable and high-quality image display with improved contrast can be obtained.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to FIGS.
[0028]
  The structure of a plasma display panel (hereinafter referred to as a panel) is shown in FIG. Also,OneFIG. 3 shows an electrode structure for the discharge cell. In FIG.Scan electrode 4 includes a discharge start portion 41 close to the discharge gap and a discharge end portion 42 far from the discharge gap, and sustain electrode 5 also includes a discharge start portion 51 close to the discharge gap and a discharge end portion 52 far from the discharge gap. Has been. This structure is functionally separated by the discharge start portions 41 and 51 forming the discharge gap and the discharge termination portions 42 and 52 located outside the discharge gap portions,By reducing the area of the electrode, there is an effect of reducing discharge current and improving discharge efficiency.
[0029]
  Here, separation in terms of function means that a potential distribution is generated on the surface of the first dielectric layer 6 by the voltage applied to each electrode, and the wall charge accumulated thereby is close to the discharge gap and its portion. Represents changing with the outside. Thereby, as will be described later, the control of the wall charges by the discharge can be performed independently in each separated portion. Also,The discharge start portions 41 and 51 forming the discharge gap lower the discharge start voltage, and the discharge termination portions 42 and 52 far from the discharge gapThe area where the discharge spreads is determined.
[0030]
  Next, in the present invention, it is important to selectively use two types of discharges that occur depending on the voltage waveform applied to the electrodes. The two types of discharges are discharges that occur by first applying a voltage sufficiently higher than the discharge start voltage to the discharge space. Hereinafter, this is referred to as “strong discharge”. The second is discharge that occurs by applying a voltage that gradually increases from a voltage lower than the discharge start voltage to a voltage higher than the discharge start voltage in the discharge space. Hereinafter, this is referred to as “weak discharge”.
[0031]
  The difference between these discharges will be described with reference to FIG. FIG.OneThe sectional view in the direction perpendicular to the scan electrode 4 of the discharge cell is shown, and for the sake of simplicity, only the scan electrode 4, the sustain electrode 5, the first dielectric layer 6 and the discharge space are shown. Here, it is assumed that wall charges are not accumulated in the first dielectric layer 6 before the discharge starts. When wall charges are accumulated before discharge, the voltage applied to the discharge space may be considered as a value obtained by superimposing the voltage due to wall charges on the externally applied voltages V1 and V2.
[0032]
  When the scan electrode 4 and the sustain electrode 5 are arranged in the same plane, the electric field strength becomes strongest when a voltage is applied between the two electrodes. It is a part (X of Fig.4 (a)) near a gap. In the portion far from the discharge gap (Y in FIG. 4A), the electric field strength is naturally weaker than that.
[0033]
  As shown in FIG. 4B, when the applied voltage V1 is sufficiently higher than the discharge start voltage Vf in the discharge space (in this case, the voltage at which the X portion where discharge is most likely to occur in the discharge space starts discharge), The Y portion away from the gap also reaches the discharge start voltage Vf, or the discharge start voltage Vf decreases due to the inducing action of the discharge occurring in the X portion, and the discharge spreads quickly throughout the discharge space. In this case, the wall charges are distributed over a wide range of the first dielectric layer 6 covering both electrodes, and are arranged so as to cancel the voltage V1 applied from the outside, so that the electric field in the discharge space is close to 0 (FIG. 4). (C)). This is a strong discharge.
[0034]
  As shown in FIG. 4D, when the applied voltage V2 is a voltage slightly exceeding the discharge start voltage Vf of the discharge space, the discharge starts at the X portion, but the electric field is changed to the discharge start voltage Vf by the movement of the wall charges. The discharge converges at a point below that. Therefore, the electric field strength in the X portion is held in a state slightly lower than the discharge start voltage Vf (FIG. 4 (e)). This is a weak discharge.
[0035]
  Although it is difficult to control the application of the voltage V2 slightly exceeding the discharge start voltage Vf, the applied voltage V2 has a voltage waveform that gradually changes from a voltage lower than the discharge start voltage Vf toward a higher voltage. It is possible to adjust the arrangement of the wall charges by continuously performing the weak discharge and performing the discharge while maintaining the electric field in the discharge space close to the discharge start voltage Vf. This method is applied to a driving method disclosed in, for example, Japanese translation of PCT publication No. 2000-501199.
[0036]
  As shown in FIG. 4E, the weak discharge is characterized by occurring in a spatially limited region. When this weak discharge is applied to the electrode structure of FIG. 3, the discharge due to the weak discharge is less likely to spread further away from the discharge gap, and the discharge can be limited only to the vicinity of the discharge gap. Therefore, by utilizing this, the discharge in the portion near the discharge gap, the discharge in the far portion, and the wall charge can be controlled independently.
[0037]
  The present invention combines the driving method applied to the electrode structure in which the function is separated into the portion near and far from the discharge gap in FIG. 3 and the above-described difference between the two types of discharge, strong discharge and weak discharge. Is.
[0038]
  Next, the driving method of the present invention in which these two types of discharges are applied to the electrode structure of FIG. 3 will be described with reference to FIGS. 1, 5, and 6. FIG.
[0039]
  FIG. 1 shows voltage waveforms in the driving method according to the embodiment of the present invention. 1A is a scanning electrode 4, FIG. 1B is a sustain electrode 5, FIG. 1C is a waveform applied to the writing electrode 11, and FIG. To express. The times t1 to t6 shown here correspond to the times in FIG. The operation based on this voltage waveform will be described with reference to FIG. FIG. 5 is similar to FIG.One6 is a cross-sectional view of the discharge cell taken along the write electrode 11, and only the scan electrode 4, the sustain electrode 5, the first dielectric layer 6, the phosphor layer 9, and the write electrode 11 are shown for simplicity. Further, in order to show a functionally separated electrode structure, the scan electrode 4 and the sustain electrode 5 are divided into portions 41 and 51 near the discharge gap and portions 42 and 52 far from the discharge gap, respectively.
[0040]
  First, at time t1 of the first initialization period, which is the first initialization step, the scan electrode 4The first potential in the negative directionVoltage -Vset1 is applied to sustain electrode 5Second potential in the positive directionThe voltage Vset2 is applied. As a result, a strong discharge occurs between the scan electrode 4 and the sustain electrode 5, and is close to the discharge gap as shown in FIG.Discharge start part41, 51, far from the discharge gapDischarge endWall charges are accumulated in both 42 and 52.
[0041]
  Next, the scanning electrode 4A slowly changing voltage is applied from the first potential -Vset1 toward the positive third potential Vset3 with a predetermined rate of change, and the second potential Vset2 to Vset2 is applied to the sustain electrode 5. Apply a slowly changing voltage with a predetermined rate of change toward Ve, which is a lower fourth voltage.. Here, the gradual change means a change in which the weak discharge described above occurs continuously.
[0042]
  The predetermined change rate is 10 V / microsecond or less. If this rate of change is too rapid, the discharge will end immediately due to a strong discharge.
[0043]
  Thus, with a predetermined rate of changeFrom voltage change during the first initialization stepBy applying a slowly changing voltage, as shown in FIG. 5C, in the second initialization period, which is the second initialization step following the first initialization period, the discharge start portion 41 close to the discharge gap. , 51 is a weak discharge. By this discharge, the discharge start portion 41 near the discharge gap of the scan electrode 4 changes from positive polarity to negative polarity. Further, the discharge start portion 51 close to the discharge gap of the sustain electrode 5 changes from negative polarity to positive polarity. Since this discharge can be limited only to a portion close to the discharge gap as described above, wall charges accumulated in a portion far from the discharge gap in the previous discharge can be held as they are.
[0044]
  As shown in FIG. 5D, at the time t3 when the initialization period (first initialization period + second initialization period), which is the initialization step, is completed by the operation so far, a portion close to the discharge gap. The discharge start portions 41 and 51 and the discharge termination portions 42 and 52 that are far from the discharge gap have different wall charges.
[0045]
  After this, the potential of the scan electrode 4 is changed to -Va. Even in this potential change, the discharge start portion is kept close to the discharge start voltage by weak discharge.
[0046]
  During the writing period, which is a subsequent writing step, the bias voltage Vscan is applied to the scanning electrodes 4 other than the row in which writing is performed so that no discharge occurs. The scanning electrode 4 in the row where writing is performed, except for the bias voltage Vscan,Negative potential voltage−Va and at the same time the write electrode 11Positive voltageVd is applied. First, discharge starts between the write electrode 11 and the discharge start portion 41 of the scan electrode 4, and the discharge start portion 41 of the scan electrode 4 and the sustain electrode 5 that is adjusted to a state close to the discharge start voltage during the initialization period. , 51 is also discharged. Since the polarity of the wall charges accumulated in the discharge terminal portions 42 and 52 is opposite, the discharge does not reach here.
[0047]
  As a result of this writing discharge, the wall charges accumulated in the two portions of the scan electrode 4 and the two portions of the sustain electrode 5 have the same polarity, as shown in FIG. At t6), the scanning electrode 4Positive directionBy grounding the voltage Vs and the sustain electrode 5, a discharge spreading over the entire electrode can be generated.
[0048]
  Since the non-selection discharge cell does not cause the write discharge, the wall charge distribution at the start of the sustain period (time t6) is as shown in FIG. Therefore, even if the sustain pulse is applied, the discharge cannot be started.
[0049]
  In the case of the conventional driving method, as shown in FIG. On the other hand, the write discharge of the present invention occurs only at the discharge start portion that is a portion close to the discharge gap as shown in FIG. In addition, since the spatial extension of the write discharge is small, the write discharge hardly affects the adjacent discharge cells, and the charge moves to the adjacent discharge cells to change the wall charge. Talk is difficult to occur.
[0050]
  Next, the circuit configuration of the driving method of the present invention is shown in the block diagram of FIG. In FIG. 6, signals from the initialization waveform generation circuit and the sustain pulse generation circuit are applied to the sustain electrode 5, and signals from the initialization waveform generation circuit and the sustain pulse generation circuit are applied to the scan electrode 4 via the scan pulse generation circuit. In addition, a signal from the write pulse generation circuit is applied to the write electrode 11.
[0051]
  Next, the operation in the subfield of the present invention in which the contrast is further improved in addition to the effect of preventing the above-described crosstalk will be described below.
[0052]
  As shown in FIG. 9, a method called a subfield method is generally used as a panel driving method. In this method, one field time is divided into a plurality of subfields having different weights, and gradation display is performed by a combination of subfields to be lit.
[0053]
  In general, the initialization period and the writing period are common to each subfield, and only the length of the sustain period (usually the number of pulses) differs depending on the weight of the subfield.
[0054]
  In the present embodiment, as shown in FIG. 1, the drive waveforms of the subfields after the second subfield are in the first initialization period, which is the first half of the initialization period existing in the first subfield. The negative voltage applied to the scan electrode 4 is eliminated.
[0055]
  In this case, the discharge in the first initialization period in the subfield after the second subfield is substituted with the last discharge in the sustain period. That is, in the second subfield, the sustain period in the sustain step of the immediately preceding first subfield isFor the last pulse, by applying a voltage so that wall charges of the same polarity as during the discharge in the first initialization period are accumulatedTherefore, the “strong discharge” occurring there is used as it is as the discharge in the first initialization period of the second subfield, and the portion of applying the first potential voltage in the negative direction to the scan electrode in the first initialization step is omitted. Is.
[0056]
  This discharge does not occur in the discharge cells that were not maintained during the sustain period. Therefore, each discharge cell performs a sustain discharge, discharges in initialization of the next subfield, and continues to wait until the next write period of the subfield to be lit in a state immediately before the write period. Become. In other words, the initializing discharge is discharged only during the initializing discharge of the subfield next to the maintained subfield and the initializing period of the first subfield. On the other hand, when the voltage waveform shown in FIG. 10 is applied to all the subfields in the same manner, the discharge in the first initialization period occurs in all the subfields in all the discharge cells. Since this discharge emits light regardless of display, it has been a major factor in reducing contrast. According to the present embodiment, light emission in the first initialization period in which light is emitted is only the first subfield and the subfield next to the lit subfield, and in black display only once per field. . That is, the brightness of black display is reduced by the number of subfields, and the contrast is improved.
[0057]
  A discharge cell that is lit once is lit even if there is no initialization period as in the first subfield, but the wall charge of the discharge cell that is waiting without being lit changes when it is lit from the complete initial state. In this case, one initialization period is provided in this field in order to return to the normal state even if it is done.
[0058]
  Here, the initialization by the voltage waveform of the first subfield is performed once per field and only the first subfield. However, even if the number of times is smaller, for example, once every two fields, 1 is reversed. It may be as many as twice in the field. Further, the subfield to which the initialization of the present embodiment is applied is not necessarily the first subfield. In the panel driving method of the present invention, the waveform in the writing period, the scanning order, the sustain waveform in the sustain period, and the like are arbitrary.
[0059]
  Further, as shown in FIG. 3, the panel to which the present invention is applied has an electrode arrangement order (positional relationship between the scanning electrode 4 and the sustaining electrode 5), and the partition wall 8 if the electrode structure is functionally separated. In addition, the shapes of the first dielectric layer 6, the phosphor layer 9, and the write electrode 11 are arbitrary.
[0060]
【The invention's effect】
  As described above, the present invention is a method for driving a plasma display panel in which a discharge start portion that is a portion near the discharge gap and a discharge termination portion that is a portion far from the discharge gap are formed on each of the scan electrode and the sustain electrode, One field is composed of a plurality of subfields, and the subfield includes an initialization step including a first initialization step and a second initialization step, and the scan electrode and the write electrode provided after the initialization step. A write step for selecting a discharge cell to be displayed by applying a voltage to the voltage, and a sustain step for generating a sustain discharge in the discharge cell selected in the write step to execute display, and the first initialization In the step, a negative first potential is applied to the scan electrode. A voltage having a second potential in the positive direction is applied to the sustain electrode to generate a discharge at both the discharge start portion and the discharge end portion. Thereafter, in the second initialization step, the scan electrode has the first potential. Toward the positive third potentialVoltage that changes more slowly than during the first initialization stepTo the sustain electrode from the second potential toward a fourth potential lower than the second potential.Voltage that changes more slowly than during the first initialization stepIn the write step, a negative voltage is applied to the scan electrode for writing and a positive voltage is applied to the write electrode in the write step. Between the write electrode and the discharge start portion of the scan electrodeDischargeIn addition, the discharge is generated between the discharge start portions of the scan electrode and the sustain electrode, thereby reducing the spatial spread of the write discharge, reducing the write discharge current, and displaying an abnormality. Crosstalk discharge can be prevented by a simple method, and furthermore, by preventing strong discharge for each subfield, the intensity of light emission independent of display is weakened, and stable high quality images with improved contrast An indication can be obtained.
[Brief description of the drawings]
FIG. 1 is a voltage waveform diagram in a driving method according to an embodiment of the present invention.
FIG. 2 is a structural diagram of a panel according to an embodiment of the present invention.
FIG. 3 is an electrode structure diagram of the panel according to the embodiment of the present invention.
FIG. 4 is a diagram for explaining strong discharge and weak discharge in the present invention.
FIG. 5 is a cross-sectional view for explaining wall charge operation in the driving method according to the embodiment of the present invention;
FIG. 6 is a block diagram showing a circuit configuration of a driving method according to the present invention.
FIG. 7 is a perspective view showing the structure of a conventional panel.
FIG. 8 is an electrode structure diagram of a conventional panel.
FIG. 9 is a diagram showing a subfield division method in a conventional panel driving method.
FIG. 10 is a diagram showing an example of a driving voltage waveform of a conventional panel
FIG. 11 is a cross-sectional view for explaining wall charge operation in a conventional driving method;
[Explanation of symbols]
  1 panel
  2 First substrate
  3 Second substrate
  4 Scanning electrodes
  4A, 5A metal busbar
  4B, 5B transparent electrode
  5 Maintenance electrode
  6 First dielectric layer
  7 Protective film
  8 Bulkhead
  9 Phosphor layer
  10 Second dielectric layer
  11 Write electrode
  41 A portion of the scan electrode close to the discharge gap (discharge start portion)
  42 A portion of the scanning electrode far from the discharge gap (discharge termination portion)
  51 Part of sustain electrode close to discharge gap (discharge start part)
  52 Part of sustain electrode far from discharge gap (discharge termination)

Claims (1)

A first substrate on which a scan electrode and a sustain electrode are formed opposite to each other by forming a discharge gap; and a second substrate in which a write electrode is formed in a direction orthogonal to the scan electrode and the sustain electrode and disposed opposite to the first substrate And a discharge start portion that is a portion close to the discharge gap and a discharge termination portion that is a portion far from the discharge gap are formed on each of the scan electrode and the sustain electrode. One field is constituted by a plurality of subfields, and the subfield is provided after an initialization step including a first initialization step and a second initialization step, and after the initialization step and the scan electrode and the writing A writing step of selecting a discharge cell to be displayed by applying a voltage to the electrode; A sustain step of generating a sustain discharge in the discharge cell selected in the step and executing display, and in the first initialization step, a negative first potential is applied to the scan electrode. Then, by applying a voltage having a second potential in the positive direction to the sustain electrode, a discharge is generated at both the discharge start portion and the discharge end portion, and then in the second initialization step, the scan electrode has the first potential. A voltage that gradually changes from the potential toward the third potential in the positive direction is applied to the sustain electrode from the second potential toward the fourth potential that is lower than the second potential. wherein to generate discharge only in the discharge start part by applying a first voltage that changes slowly than during the initialization step, in said writing step, the scanning electrodes for writing By applying a positive voltage to the write electrode to apply a negative voltage, with a discharge is generated between the discharge start part of the write electrode and the scanning electrode, the discharge of the scan electrodes and sustain electrodes A discharge is generated between the start portions, and at least one subfield of the plurality of subfields is the last pulse in the sustaining step of the immediately preceding subfield during the discharge in the first initialization step. The plasma is characterized in that a voltage is applied so that wall charges having the same polarity as in the first electrode are accumulated, so that a portion of applying a first potential voltage in the negative direction to the scan electrode is omitted in the first initialization step. Display panel drive method.

Images