KR100524314B1 - Method of Driving Plasma Display Panel - Google Patents

Abstract

The present invention relates to a method of driving a plasma display panel that can improve contrast and reduce power consumption.

The driving method of the plasma display panel according to the present invention includes supplying a rising ramp waveform to the scan electrodes to position wall charges within a quadrant of the voltage curve, applying a base potential to the scan electrodes, and scanning electrodes. Applying a positive DC voltage to the sustain electrodes when the ground potential is applied to the sustain electrodes; and supplying a falling ramp waveform descending from the ground potential to the scan electrodes to position the wall charges in the center of the voltage curve. . The rising ramp waveform rises rapidly up to the first voltage and gradually rises with a slope up to the peak voltage. The peak voltage is a second voltage which is a sum of a voltage at which discharge is started between the sustain electrode and the scan electrode when a voltage is applied to the sustain electrode and a voltage at which discharge is initiated between the scan electrode and the sustain electrode when a voltage is applied to the scan electrode. And a third voltage which is the sum of the voltage at which the discharge is started between the address electrode and the scan electrode when the voltage is applied to the address electrode and the voltage at which the discharge is initiated between the scan electrode and the address electrode when the voltage is applied to the scan electrode. It is set to a voltage value below the voltage.

Description

Driving Method of Plasma Display Panel {Method of Driving Plasma Display Panel}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a plasma display panel, and more particularly, to a method for driving a plasma display panel that can improve contrast and reduce power consumption.

Plasma Display Panels (hereinafter referred to as "PDPs") are characterized by emitting phosphors by 147 nm ultraviolet rays generated during discharge of an inert mixed gas such as He + Xe, Ne + Xe or He + Xe + Ne. An image containing graphics is displayed. Such a PDP is not only thin and easy to enlarge, but also greatly improved in quality due to recent technology development. In particular, the three-electrode AC surface discharge type PDP has advantages of low voltage driving and long life because wall charges are accumulated on the surface during discharge and protect the electrodes from sputtering caused by the discharge.

Referring to FIG. 1, a discharge cell of a three-electrode AC surface discharge type PDP includes a scan electrode Y and a sustain electrode Z formed on the upper substrate 10, and an address electrode formed on the lower substrate 18. X). Each of the scan electrode Y and the sustain electrode Z has a line width smaller than the line widths of the transparent electrodes 12Y and 12Z and the transparent electrodes 12Y and 12Z and is formed at one edge of the transparent electrode 13Y, 13Z).

The transparent electrodes 12Y and 12Z are usually formed on the upper substrate 10 by indium tin oxide (ITO). The metal bus electrodes 13Y and 13Z are usually formed of metals such as chromium (Cr) and formed on the transparent electrodes 12Y and 12Z to reduce voltage drop caused by the transparent electrodes 12Y and 12Z having high resistance. The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan electrode Y and the sustain electrode Z side by side. In the upper dielectric layer 14, wall charges generated during plasma discharge are accumulated. The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used.

The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode X is formed, and the phosphor layer 26 is coated on the surfaces of the lower dielectric layer 22 and the partition wall 24. The address electrode X is formed in the direction crossing the scan electrode Y and the sustain electrode Z. The partition wall 24 is formed in parallel with the address electrode X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert mixed gas is injected into the discharge space provided between the upper and lower substrates 10 and 18 and the partition wall 24.

The PDP is time-divisionally driven by dividing one frame into several subfields having different number of emission times in order to implement grayscale of an image. Each subfield is divided into an initialization period for initializing the full screen, an address period for selecting a scan line and selecting a cell in the selected scan line, and a sustain period for implementing gray levels according to the number of discharges.

Here, the initialization period is divided into a setup period in which the rising ramp waveform is supplied and a set down period in which the falling lamp waveform is supplied. For example, when the image is to be displayed with 256 gray levels, as shown in FIG. 2, the frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields SF1 to SF8. As described above, each of the eight subfields SF1 to SF8 is divided into an initialization period, an address period, and a sustain period. The initialization period and the address period of each subfield are the same for each subfield, while the sustain period is increased at a rate of 2 ⁿ (n = 0,1,2,3,4,5,6,7) in each subfield. .

3 shows driving waveforms of a PDP supplied to two subfields.

Referring to FIG. 3, the PDP is driven by being divided into an initialization period for initializing the full screen, an address period for selecting a cell, and a sustain period for maintaining discharge of the selected cell.

In the initialization period, the rising ramp waveform Ramp-up is applied to all the scan electrodes Y simultaneously. This rising ramp waveform (Ramp-up) causes a slight discharge in the cells of the full screen to generate wall charges in the cells. During the set down period, after the rising ramp waveform Ramp-up is supplied, the falling ramp waveform Ramp-down falling at the positive voltage lower than the peak voltage of the rising ramp waveform Ramp-up is applied to the scan electrodes Y. It is applied at the same time. Ramp-down generates weak erase discharges in the cells, thereby eliminating unnecessary charges during wall charges and space charges generated by setup discharges, and uniformly distributing the wall charges required for address discharges in the cells of the full screen. Will remain.

In the address period, a negative scan pulse scan is sequentially applied to the scan electrodes Y and a positive data pulse data is applied to the address electrodes X. As the voltage difference between the scan pulse and the data pulse and the wall voltage generated in the initialization period are added, an address discharge is generated in the cell to which the data pulse is applied. Wall charges are generated in the cells selected by the address discharge.

On the other hand, the positive electrode DC voltage of the sustain voltage level Vs is supplied to the sustain electrodes Z during the set down period and the address period.

In the sustain period, sustain pulses sus are alternately applied to the scan electrodes Y and the sustain electrodes Z. FIG. Then, the cell selected by the address discharge is sustained in the form of surface discharge between the scan electrode Y and the sustain electrode Z each time the sustain pulse sus is applied while the wall voltage and the sustain pulse sus in the cell are added. Discharge occurs. Finally, after the sustain discharge is completed, an erase ramp waveform (erase) having a small pulse width is supplied to the sustain electrode Z to erase wall charges in the cell.

Here, the discharge generation principle of the sustain period and the wall charge initialization principle of the initialization period will be described in detail using a hexagonal voltage curve as shown in FIG. 4. Here, the Vt close curve is used as a method for measuring the discharge generation principle and the voltage margin of the PDP.

In FIG. 4, the hexagonal region inside the voltage curve is a region in which the cell voltage inside the discharge cell is shifted, and no discharge occurs when the cell voltage is located in the hexagonal inner region (ie, when the cell voltage is located in the hexagonal outer region). And (Y) indicates the direction in which the cell voltage moves when a negative voltage is applied to the scan electrode (Y). Similarly, each of Y (+), X (+), X (-), Z (+), and Z (-) is a negative electrode or a positive electrode for the scan electrode Y, the address electrode X, and the sustain electrode Z. It indicates the direction in which the cell voltage moves when the voltage of the castle is applied.

The Vtxy displayed in the first quadrant opposite discharge region of the voltage curve graph represents a voltage at which discharge starts between the address electrode X and the scan electrode Y when a voltage is applied to the address electrode X. FIG. Therefore, the straight line representing the first quadrant opposite discharge region of the voltage curve graph is set to a length equal to the voltage at which the discharge between the address electrode X and the scan electrode Y is started. Vtzy, which is displayed in the quadrant surface discharge region of the voltage curve graph, indicates a voltage at which discharge starts between the sustain electrode Z and the scan electrode Y when a voltage is applied to the sustain electrode Z. FIG. Similarly, Vtxz, Vtzx, Vtyz, and Vtyx each represent a discharge start voltage between the electrodes. On the other hand, the voltages of Vtxy, Vtzy, Vtxz, Vtzx, Vtyz, and Vtyx vary slightly from panel to panel (by cell size and process deviation), and accordingly, the shape of the voltage curve varies slightly.

Referring to the operation of the sustain period, the wall charges in the discharge cells in which the address discharge is generated are located in the third quadrant of the graph as shown in FIG. Subsequently, when the positive sustain pulse is applied to the scan electrode Y as shown in FIG. 3, the voltage values of the wall charges positioned in the third quadrant and the voltage values of the positive sustain pulse are added to the cell voltage. It moves by passing through the surface discharge area located in (that is, moving to the Y (+) side). In this case, sustain discharge is generated between the scan electrode Y and the sustain electrode Z in the discharge cells.

After the sustain discharge is generated, the wall charges are located in the first quadrant of the graph as shown in FIG. Here, since the sustain discharge is generated strongly, the wall charges are located in the first quadrant of the graph spaced apart by approximately the sustain voltage Vs in the center region of the voltage curve. Subsequently, when the positive sustain pulse is applied to the sustain electrode Z, the voltage values of the wall charges positioned in the first quadrant and the voltage values of the positive sustain pulse are added together, so that the cell voltage is located in the first quadrant of the graph as shown in FIG. 6. It is moved via the discharge area (i.e., moved to the Z (+) side). At this time, sustain discharge is generated between the sustain electrode Z and the scan electrode Y in the discharge cells.

On the other hand, after the sustain discharge is generated, the wall charges are located in the third quadrant of the graph as shown in FIG. Here, since the sustain discharge is strongly generated, the wall charges are located slightly lower, that is, in the third quadrant of the graph, at a distance separated by the sustain voltage (Vs) from the center region of the voltage curve to the -X axis. In fact, in the sustain period, the sustain discharge is generated by repeating the processes as shown in FIGS. 5 and 6 a predetermined number of times.

After the sustain discharge is completed, the wall charges are positioned in the first quadrant of the graph as shown in FIG. 7 (that is, the last sustain pulse is applied to the scan electrode Y). After the sustain discharge, the erase ramp waveform (erase) is applied to the sustain electrodes Z. ) Is supplied. When the erase lamp waveform (erase) is supplied to the sustain electrode (Z), the cell voltage is moved via the surface discharge region of the first quadrant of the graph (that is, moved to the Z (+) side) as shown in FIG. Here, a weak discharge (i.e., a ramp waveform) is generated in the cell, and the cell voltage is moved through the quadrant surface discharge area of the graph. Then, the wall charges are moved to the position of A1 by moving at a slope of 1/2.

That is, after the erase discharge is completed, the wall charges are moved to the position of A1 as shown in FIG. 8. Then, the wall charges of the cells in which the sustain discharge has not occurred in the sustain period (that is, the cells in which the address discharge has not occurred in the previous subfield) maintain the position of A2 in FIG. 8 (that is, the address discharge has not occurred). The wall charges of the cells maintain the position of A2 from the initialization period of the previous subfills to the initialization period of the next subfield).

Thereafter, the rising ramp waveform Ramp-up is supplied to the scan electrodes Y. When the rising ramp waveform Ramp-up is supplied to the scan electrodes Y, the cell voltages of the discharge cells that are discharged in the sustain period of the previous subfield are passed through the surface discharge region of three quadrants from A1 (i.e., Move to +) side to move. Here, when the cell voltage passes through the surface discharge region of the three quadrants of the graph (weak weak discharge due to the lamp pulse), the wall charges move at a slope of 1/2. Thus, the wall charges located at the point of A1 are moved to the position of A3 (the time at which the cell voltage is moved to point C). The cell voltage is lowered to point C of the graph because it must be located in the voltage curve. Here, when the cell voltage is located at the vertex of the third quadrant (ie, point C), the wall charges move with a slope of one. Thus, the wall charges located at the point of A3 are moved to the point B with a slope of one.

On the other hand, when the rising ramp waveform Ramp-up is supplied to the scan electrodes Y, the cell voltages of the discharge cells in which the sustain discharge is not generated in the previous subfield are passed through the surface discharge region of the third quadrant from the point of A2 (that is, , Move to the Y (+) side). Here, when the cell voltage passes through the surface discharge region of the third quadrant of the graph (weak weak discharge due to the lamp pulse), the wall charges are moved at a slope of 1/2. Thus, the wall charges located at the point of A2 are moved to the position of A4 (the time at which the cell voltage is moved to point C). The cell voltage is lowered to point C of the graph because it must be located in the voltage curve. Here, when the cell voltage is located at the vertex of the third quadrant (ie, point C), the wall charges move with a slope of one. Thus, the wall charges located at the point of A4 are moved to the point B with a slope of one.

That is, when the rising ramp waveform (Ramp-up) is supplied in the initialization period, the wall charges of all the discharge cells are moved to the point B. Thereafter, a falling ramp waveform Ramp-down falling from the rising ramp waveform Ramp-up is supplied to the scan electrodes Y.

 When the falling ramp waveform Ramp-down is supplied to the scan electrodes Y, the cell voltage located at the point C is moved to the point C1 as shown in FIG. 9. Then, a positive voltage is applied to the sustain electrode Z when the falling ramp waveform Ramp-down falls with a slope. Then, the cell voltage located at the point C1 is moved to the point of C2. Then, since the ramp ramp down continues, the cell voltage is moved from the point of C2 through the surface discharge region of the first quadrant. Here, when the cell voltage passes through the surface discharge region of the first quadrant, the wall charges move at a slope of 1/2. Thus, the wall charges that were located at point B are moved to the position of A2. That is, when the ramp ramp down is supplied in the initialization period, the wall charges located at the point B are moved to the point A2 to initialize the discharge cells.

That is, in the conventional PDP, the wall charges of all the discharge cells are initialized to the point of A2 by continuously supplying the rising ramp waveform and the falling ramp waveform during the initialization period. To this end, the conventional PDP needs to supply a ramp-up ramp having a high voltage value for many hours. When a ramp-up having a high voltage value is applied as described above, a lot of light is generated by the discharge generated during the initialization period, thereby causing a problem of lowering the contrast. In addition, when a high voltage is applied during the initialization period, a lot of power consumption is consumed. In addition, since a ramp-up has to be applied for many hours, a problem arises in that it is not possible to allocate sufficient time to the sustain period actually required for driving.

Accordingly, it is an object of the present invention to provide a method of driving a PDP that can improve contrast and reduce power consumption.

In order to achieve the above object, the driving method of the PDP according to the present invention is to supply rising ramp waveforms to the scan electrodes to position wall charges within a quadrant of the voltage curve, and to apply a ground potential to the scan electrodes. Applying a positive DC voltage to the sustain electrodes when the ground potential is applied to the scan electrodes, and supplying the wall electrodes to the center of the voltage curve by supplying the scan electrodes with a falling ramp waveform that descends from the ground potential. Positioning.

The rising ramp waveform rises rapidly up to the first voltage and gradually rises with a slope up to the peak voltage.

The voltage value of the first voltage is set below the voltage value at which discharge starts between the sustain electrode and the scan electrode when a voltage is applied to the sustain electrode.

The peak voltage is a second voltage which is a sum of a voltage at which discharge is started between the sustain electrode and the scan electrode when a voltage is applied to the sustain electrode and a voltage at which discharge is initiated between the scan electrode and the sustain electrode when a voltage is applied to the scan electrode. And a third voltage which is the sum of the voltage at which the discharge is started between the address electrode and the scan electrode when the voltage is applied to the address electrode and the voltage at which the discharge is initiated between the scan electrode and the address electrode when the voltage is applied to the scan electrode. It is set to a voltage value below the voltage.

The voltage value of the positive DC voltage applied to the sustain electrodes is set to 100V or less.

The falling ramp waveform gradually falls to the second negative voltage having a slope.

The sum voltage of the absolute voltage value of the second negative voltage and the positive DC voltage is maintained when the voltage is applied to the address electrode and the scan electrode or when the voltage is applied to the sustain electrode when the voltage is applied to the address electrode. It is set between the voltage at which discharge is started between the electrode and the scan electrode.

Scan pulses that fall from the first negative voltage to the second negative voltage are supplied to the scan electrodes during the address period subsequent to the initialization period.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 10 to 12.

10 is a waveform diagram illustrating a method of driving a PDP according to an embodiment of the present invention.

Referring to FIG. 10, a PDP according to an embodiment of the present invention is driven by being divided into an initialization period for initializing a full screen, an address period for selecting a cell, and a sustain period for maintaining discharge of the selected cell.

In the setup period during the initialization period, a positive rising ramp waveform Ramp-up is applied to the scan electrodes Y. This rising ramp waveform (Ramp-up) causes a weak discharge in the cells of the full screen to form wall charges in the cells. Here, the rising ramp waveform Ramp-up rapidly rises to the first voltage V1 and then rises with a slope from the first voltage V1 to the second voltage V2 which is the peak voltage.

When the discharge is generated in the setup period in detail using the voltage curve Vt close curve, first, the wall charges of the on-cells in which the discharge is generated during the sustain period of the previous subfield are located at the point A1 as shown in FIG. Then, the wall charges of the off-cells in which the discharge has not occurred during the sustain period of the previous subfield are located at a point D1 which is the center of the voltage curve. (The wall charges of the off-cells are initialized in the next subfield from the initialization period of the previous subfield. Here, the wall charges of the offcells may flow slightly from the point of D1 due to various requirements such as the process deviation of the discharge cell and the size of the cell.

When the voltages of the scan electrodes Y are raised to the first voltage V1, the cell voltages of the on cells are moved from the point A1 to the surface discharge region (that is, moved to the Y (+) side) as shown in FIG. 11. . Here, the voltage value of the first voltage V1 is set to a voltage value at which the cell voltages of the on cells are located in the voltage curve. For example, the voltage value of the first voltage V1 is set equal to or lower than Vtyz (the voltage at which discharge starts between the scan electrode Y and the sustain electrode Z when a voltage is applied to the scan electrode Y). (V1≤Vtyz)

Thereafter, the voltages of the scan electrodes Y gradually rise from the first voltage V1 to the second voltage V2. Then, the cell voltages of the on cells are moved via the surface discharge region (that is, moved to the Y (+) side) of the three quadrants. When the cell voltages of the on-cells are moved through the three-quadrant area, the wall charges located at the point A1 are shifted by one half of the inclination. Thus, the wall charges located at the point of A1 are moved to the position of D3 (the time at which the cell voltage is moved to point C). And, the cell voltage is lowered to point C of the graph because it must be located in the voltage curve. Here, when the cell voltage is located at the vertex of the third quadrant (ie, point C), the wall charges move with a slope of one. Thus, the wall charges located at the point of D3 are moved to the point of D4 located inside the voltage curve at a slope of one.

On the other hand, the voltage value of the second voltage (V2) is equal to the lower voltage of the first sum voltage of Vtzy + Vtyz and the second sum voltage of Vtxy + Vtyx so that the cell voltage of the on cells can be moved to the point of D4 or (V2 ≤ min {(Vtzy + Vtyz), (Vtxy + Vtyx)}) In other words, the second voltage V2 is set equal to or lower than the lower one of the first and second sum voltages. The cell voltage of the on cells is moved to the point of D4. On the other hand, Vtzy is a voltage at which discharge is initiated between sustain electrode Z and scan electrode Y when voltage is applied to sustain electrode Z, and Vtyz is scan electrode Y when voltage is applied to scan electrode Y. ) Is a voltage at which discharge is initiated between the sustain electrode Z, Vtxy is a voltage at which discharge is initiated between the address electrode X and the scan electrode Y when a voltage is applied to the address electrode X, and Vtyx is a scan electrode ( The voltage at which discharge starts between the scan electrode Y and the address electrode X when a voltage is applied to Y).

On the other hand, when the voltages of the scan electrodes Y rise to the first voltage V1, the cell voltages of the off-cells are in three surface quadrants (i.e., move toward the Y (+) side) from the point D1 as shown in FIG. (In this case, the cell voltages of the offcells are moved to a point approximately adjacent to the point C). Here, the voltage value of the first voltage V1 is a voltage value at which the cell voltages of the offcells are located in the voltage curve. Is set. For example, the voltage value of the first voltage V1 is set equal to or lower than Vtyz (the voltage at which discharge starts between the scan electrode Y and the sustain electrode Z when a voltage is applied to the scan electrode Y). (V1≤Vtyz)

Thereafter, the voltages of the scan electrodes Y gradually rise from the first voltage V1 to the second voltage V2. Then, the cell voltages of the off-cells are moved via the surface discharge region (that is, moved to the Y (+) side) of the three quadrants. When the cell voltages of the offcells are moved through the surface discharge area, the three quadrants move the wall charges located at the point of D1 with a slope of 1/2. Therefore, the wall charges located at the point of D1 are moved to the position of D2 (the time at which the cell voltage is moved to point C). Then, the cell voltage is lowered to point C of the graph because it must be located in the voltage curve. Here, when the cell voltage is located at the vertex of the third quadrant (ie, point C), the wall charges move with a slope of one. Thus, the wall charges located at the point of D2 are moved to the point of D4 located inside the voltage curve at a slope of one. That is, when the ramp ramp is supplied during the setup period, the wall charges of all the discharge cells are moved to the point D4.

On the other hand, the voltage value of the second voltage (V2) is equal to or lower than the first voltage of Vtzy + Vtyz and the second voltage of Vtxy + Vtyx so that the cell voltage of the off-cells can be moved to the point of D4 Or is set low. (V2? Min {(Vtzy + Vtyz), (Vtxy + Vtyx)}) In other words, the second voltage V2 is equal to or lower than the lower one of the first and second sum voltages. The cell voltage of the on cells is set to move to the point of D4. On the other hand, Vtzy is a voltage at which discharge is initiated between sustain electrode Z and scan electrode Y when voltage is applied to sustain electrode Z, and Vtyz is scan electrode Y when voltage is applied to scan electrode Y. ) Is a voltage at which discharge is initiated between the sustain electrode Z, Vtxy is a voltage at which discharge is initiated between the address electrode X and the scan electrode Y when a voltage is applied to the address electrode X, and Vtyx is a scan electrode ( The voltage at which discharge starts between the scan electrode Y and the address electrode X when a voltage is applied to Y).

After the wall charges of the on-cell and off-cells converge to the point of D4, the voltage value of the scan electrodes Y drops rapidly to the third voltage V3 in the setdown period. Here, the voltage value of the third voltage V3 is set to the ground potential GND. In fact, when the voltage values of the scan electrodes Y are rapidly lowered to the third voltage V3, the cell voltage is rapidly moved from the point C to the point E1 as shown in FIG. On the other hand, since the wall charges converge to the point of D4 inside the voltage curve, even if the cell voltage drops rapidly to the third voltage V3, self-erasing discharge does not occur in the cells. If the voltages of the scan electrodes Y are lowered to the ground potential GND, self erasing discharge occurs.)

When the voltage values of the scan electrodes Y rapidly fall to the third voltage V3, a positive DC voltage having the fifth voltage V5 is applied to the sustain electrodes Z. (Set-down period) When the positive DC voltage having the fifth voltage V5 is applied to the field Z, the cell voltage located at the point of E1 is moved to the point of E2. Here, the fifth voltage V5 is set to a voltage value at which the cell voltage is located inside the voltage curve. To this end, the voltage value of the fifth voltage V5 is set to a voltage value of less than 100V (voltage lower than the sustain voltage).

After the voltage value drops rapidly to the third voltage V3 at the scan electrodes Y, the falling ramp waveform Ramp- is lowered to the scan electrodes Y with a slope to the fourth voltage V−4 of the negative polarity. down) is applied. Then, the cell voltage is moved via the surface discharge region (that is, moved to the Y (-) side) in one quadrant. When the cell voltage is moved through the surface discharge area of the first quadrant, the wall charges located at the point of D4 are shifted by 1/2 the slope. Therefore, the wall charges located at the point of D4 are moved to the position of D5 (the time when the cell voltage is moved to the vertex of the first quadrant). And, since the cell voltage has to be located within the voltage curve, it is moved to the vertex of the graph. Here, when the cell voltage is located at the vertex of the first quadrant, the wall charges move with a slope of one. Thus, the wall charges located at the point of D5 are moved to the point of D1 with a slope of one. That is, after the initialization period, the wall charges of all the discharge cells converge to the point of D1. On the other hand, the absolute voltage value of the fourth voltage (-V4) is set so that the wall charges can be moved to the point of D1. To this end, the absolute fourth voltage V4 is set larger than the absolute fifth voltage V5.

In the present invention as described above, since the voltage value of the second voltage V2 is set lower than that of the related art, a weaker discharge is generated during the set-up period, thereby improving the contrast. In the present invention, since the voltage can be drastically lowered from the second voltage V2 to the ground potential GND, the initializing period can be shortened compared to the conventional one, and thus sufficient time is allocated to the sustain period which contributes to luminance. Can be.

As described above, according to the driving method of the PDP according to the present invention, when the rising ramp waveform is supplied by setting the peak voltage value of the rising ramp waveform to be lower than the conventional one, the wall charges can be located inside one quadrant of the voltage curve. Thereby, contrast can be improved. In the present invention, since the voltage can be drastically lowered from the peak value voltage to the ground potential, the initialization period can be shortened compared with the conventional one, and thus sufficient time can be allocated to the sustain period which contributes to the luminance.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

1 is a perspective view showing a discharge cell structure of a conventional three-electrode AC surface discharge type plasma display panel.

2 is a diagram showing an example of a luminance weight value of a subfield included in one frame.

3 is a waveform diagram showing driving waveforms applied to electrodes during a period of a subfield;

4 is a diagram showing positions of wall charges in discharge cells in which address discharge has occurred.

5 is a view illustrating a process in which a sustain discharge is generated when a sustain pulse is supplied to the wall charge shown in FIG. 4.

FIG. 6 is a view showing positions of wall charges formed by the sustain discharge of FIG. 5; FIG.

7 is a view showing a process of moving the wall charge by the erase pulse.

FIG. 8 is a view illustrating a process in which wall charges are moved by the rising ramp waveform shown in FIG. 3.

9 is a view showing a process of moving the wall charge by the falling ramp waveform shown in FIG.

10 is a waveform diagram illustrating a method of driving a plasma display panel according to an embodiment of the present invention.

FIG. 11 is a view illustrating a process in which wall charges are moved by the rising ramp waveform shown in FIG. 10.

FIG. 12 is a view illustrating a process of moving wall charges by the falling ramp waveform shown in FIG. 10.

<Description of Symbols for Main Parts of Drawings>

10: upper substrate 12Y, 12Z: transparent electrode

13Y, 13Z: bus electrode 14, 22: dielectric layer

16: protective film 18: lower substrate

24: partition 26: phosphor layer

Claims (7)

A driving method of a plasma display panel including an initialization period for initializing discharge cells, the method comprising: Supplying a rising ramp waveform to the scan electrodes that rises rapidly up to a first voltage and gradually rises up to a peak voltage to position the wall charges within a quadrant of the voltage curve; Applying a ground potential to the scan electrodes; Applying a positive DC voltage to sustain electrodes when a ground potential is applied to the scan electrodes; Supplying the falling ramp waveform descending from the base potential to the scan electrodes to position wall charges in the center of the voltage curve; The peak voltage is a voltage at which discharge is initiated between the sustain electrode and the scan electrode when a voltage is applied to the sustain electrode and a voltage at which discharge is initiated between the scan electrode and the sustain electrode when a voltage is applied to the scan electrode. A discharge voltage is started between the address electrode and the scan electrode when a voltage is applied to the address voltage and the address electrode, and a discharge is started between the scan electrode and the address electrode when a voltage is applied to the scan electrode. And a voltage value equal to or lower than a lower voltage among the third voltages which are the sum voltages of the voltages. delete The method of claim 1, And the voltage value of the first voltage is set to be equal to or less than a voltage value at which discharge starts between the scan electrode and the sustain electrode when a voltage is applied to the scan electrode. delete The method of claim 1, And a voltage value of the positive DC voltage applied to the sustain electrodes is set to 100 V or less. The method of claim 5, And said falling ramp waveform gradually falls to a second negative voltage having a slope. The method of claim 6, And the absolute voltage value of the second negative voltage is greater than the positive DC voltage.