KR100751931B1 - Plasma Display Panel and Driving Method thereof - Google Patents

Abstract

The present invention relates to a plasma display panel for stabilizing selective write discharge for data writing and a driving method thereof.

In the plasma display panel of the present invention, the electrode group included in each of the discharge cells is orthogonal to the sustain electrode and the scan electrode formed side by side on the first substrate for sustain discharge, and the scan electrode and the second substrate for the selective write discharge. And an auxiliary scan electrode formed side by side with the sustain electrode and the scan electrode on the first substrate to generate the priming discharge just before the selective write discharge.

Selective write, auxiliary scan electrode, priming discharge

Description

Plasma Display Panel and Driving Method             

1 is a cross-sectional view showing a discharge cell of a conventional three-electrode AC surface discharge plasma display panel.

FIG. 2 shows selective write discharge in the discharge cell shown in FIG. 1; FIG.

3 is a perspective view illustrating a plasma display panel according to an exemplary embodiment of the present invention.

4 is a cross-sectional view of the plasma display panel shown in FIG.

FIG. 5 is a drive waveform diagram for driving the plasma display panel shown in FIG.

<Description of Symbols for Main Parts of Drawings>

10: upper substrate 12: transparent electrode

16, 18: bus electrode 13: scanning / holding electrode

15: common holding electrode 20, 28: dielectric layer

22: protective film 24: lower substrate                 

26: address electrode 30: partition wall

32: phosphor

The present invention relates to a plasma display panel, and more particularly, to a plasma display panel for stabilizing selective write discharge for data writing and a driving method thereof.

Recently, a plasma display panel (hereinafter referred to as "PDP"), which is easy to manufacture a large panel, has attracted attention as a flat panel display device. As the PDP, a three-electrode AC surface discharge type PDP having three electrodes and using surface discharge by AC voltage is typical.

Referring to FIG. 1, a discharge cell of a three-electrode alternating surface discharge PDP includes a scan electrode 13 and a sustain electrode 15 formed on the upper substrate 10, and a data electrode formed on the lower substrate 24. 26). The scan electrode 13 includes a transparent electrode 12 for transmitting visible light and a bus electrode 16 for compensating for resistance of the transparent electrode 12. The sustain electrode 15 formed in parallel with the scan electrode 13 also includes a transparent electrode 14 and a bus electrode 18. The upper dielectric layer 20 and the passivation layer 22 are stacked on the upper substrate 10 having the scan electrode 13 and the sustain electrode 15 side by side. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 20. The passivation layer 22 prevents damage to the upper dielectric layer 20 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 20, magnesium oxide (MgO) is usually used. The data electrode 26 is formed on the lower substrate 24 in a direction crossing the scan electrode 13 and the sustain electrode 15. A lower dielectric layer 28 for wall charge accumulation is formed on the lower substrate 24 on which the data electrode 26 is formed. The partition wall 30 is formed on the lower dielectric layer 28, and the phosphor 32 is coated on the surfaces of the lower dielectric layer 28 and the partition wall 30. The partition wall 24 is formed in parallel with the data electrode 20 to prevent the ultraviolet rays and the visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor 32 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided by the upper substrate 10, the lower substrate 24, and the partition wall 30.

The discharge cells of this structure are selected by opposing discharges between the data electrodes 26 and the scan electrodes 13, and then hold the discharges by surface discharges between the scan electrodes 13 and the sustain electrodes 15. In such a discharge cell, the fluorescent material 32 emits light by ultraviolet rays generated during the sustain discharge, so that visible light is emitted to the outside of the cell. As a result, the discharge cells adjust the period during which the discharge is maintained to implement gray scale, and the PDP in which the discharge cells are arranged in a matrix form displays an image.

Such a PDP is usually driven by being divided into a plurality of subfields, and gray scale display is performed by emitting light a number of times proportional to the weight of video data in each subfield period. For example, when an image is displayed in 256 gray scales using 8-bit video data, one frame display period (for example, 1/60 second = about 16.7 msec) in each discharge cell is divided into eight subfields SF1 to SF1. SF8). Each subfield SF1 to SF8 is further divided into a reset period, an address period, and a sustain discharge period, and 1: 2: 4: 8:... The weight is given as a ratio of: 128. Here, the reset period is a period for initializing the discharge cells, the address period is a period for selecting cells by causing selective address discharge to occur according to the logic value of the video data, and the sustain discharge period is a discharge cell selected in the address period. It is a period in which discharge is maintained in the field. The reset period and the address period are equally assigned to each subfield period. In the reset period, a reset pulse is normally supplied to the scan electrode 13 to generate a reset discharge A between the scan electrode 13 and the sustain electrode 15 as shown in FIG. The wall charges formed by this reset discharge are reduced by the self-erasing discharge or the like and remain so as not to cause an erroneous discharge in the subsequent address period. Following this reset period, in the address period, the scan pulse is supplied to the scan electrode 13 and the data pulse is supplied to the data electrode 26 to generate a selective write discharge B so that data is written. Subsequently, a sustain pulse is alternately supplied to the scan electrode and the sustain electrode in the sustain discharge period to maintain the discharge in the discharge cells in which the selective write discharge is generated for a predetermined period.

In this PDP driving method, the reset discharge occurs simultaneously in all the discharge cells, so that uniform wall charges remain. In this case, the wall charges formed in the reset period gradually decrease as time passes. On the other hand, selective write discharge for data writing occurs in time sequence along the scan line. Accordingly, in each discharge cell, as the selective write discharge is generated with a predetermined time difference, a difference occurs in the amount of wall charge used for the selective write discharge, which is formed by the reset discharge. In particular, a difference occurs in the amount of wall charge used for the selective write discharge between the discharge cells in which the selective write discharge is generated in the first scan line and the discharge cells in which the selective write discharge is generated in the last scan line. As a result, the difference in the wall charge amount causes the discharge conditions of each discharge cell to be different so that uniform address discharge and sustain discharge cannot occur, which adversely affects the PDP pursuing high quality.

Accordingly, an object of the present invention is to provide a PDP and a driving method thereof capable of making uniform discharge conditions in each discharge cell by using priming charged particles.

In order to achieve the above object, the PDP according to the present invention is the electrode group included in each of the discharge cells, the sustain electrode and the scan electrode formed side by side on the first substrate for the sustain discharge, the scan electrode and for selective write discharge And an address electrode disposed on the second substrate orthogonally, and an auxiliary scan electrode formed parallel to the sustain electrode and the scan electrode on the first substrate to generate the priming discharge immediately before the selective write discharge.

In the PDP driving method according to the present invention, in the method of driving a plasma display panel including a plurality of discharge cells, each discharge cell includes a sustain electrode, a scan electrode, an auxiliary scan electrode, and an address electrode, and simultaneously in the discharge cells. Initializing the reset discharge to occur; Causing a selective write discharge to occur between the scan electrode and the data electrode immediately after the auxiliary discharge occurs between the scan electrode and the auxiliary scan electrode; And maintaining the discharge in the discharge cells in which the selective write discharge has been generated.

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

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 3 to 5.

3 is a perspective view showing a PDP structure according to an embodiment of the present invention, Figure 4 is a cross-sectional view of the PDP shown in FIG. 3 and 4 illustrate a sustain electrode 42, a scan electrode 44 and an auxiliary scan electrode 46 formed on the upper substrate 10, and a data electrode 26 formed on the lower substrate 24. ). The sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46 are arranged side by side. The sustain electrode 42 and the scan electrode 44 are formed of a transparent electrode (ITO) material, and the auxiliary scan electrode 46 is formed of a metal electrode material. The metal bus electrode 43 is formed on the sustain electrode 42, and the auxiliary scan electrode 46 serves as a conventional bus electrode in sustain discharge. In other words, the auxiliary scan electrode 46 changes the structure of the bus electrode formed on the transparent electrode of the conventional AC surface-discharge PDP upper plate and is used as an auxiliary electrode during sustain discharge. The scan electrode 44 is set smaller than the electrode width of the sustain electrode 42 because the auxiliary scan electrode 46 is added adjacent thereto. The auxiliary scan electrode 46 is set smaller than the electrode width of the scan electrode 44. The arrangement order of the sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46 is symmetrical with the adjacent discharge cells. This is to prevent the sustain discharge from generating an erroneous discharge with another electrode of an adjacent discharge cell. The upper dielectric layer 20 and the passivation layer 22 are stacked on the upper substrate 10 on which the sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46 are formed. Wall charges generated during plasma discharge are accumulated in the upper dielectric layer 20. The passivation layer 22 prevents damage to the upper dielectric layer 20 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 20, magnesium oxide (MgO) is usually used. The data electrode 26 is formed on the lower substrate 24 in a direction crossing the electrodes 42, 44, and 46 on the upper substrate 10. A lower dielectric layer 28 for wall charge accumulation is formed on the lower substrate 24 on which the data electrode 26 is formed. The partition wall 30 is formed on the lower dielectric layer 28, and the phosphor 32 is coated on the surfaces of the lower dielectric layer 28 and the partition wall 30. The partition wall 24 is formed in parallel with the data electrode 20 to prevent the ultraviolet rays and the visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor 32 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided by the upper substrate 10, the lower substrate 24, and the partition wall 30.

The discharge cell of this structure is selected by selective write discharge between the data electrode 26 and the scan electrode 13 immediately after the priming discharge between the scan electrode 44 and the auxiliary scan electrode 46. The discharge is maintained by the surface discharge between the 46 and the sustain electrode 42. In such a discharge cell, the fluorescent material 32 emits light by ultraviolet rays generated during the sustain discharge, so that visible light is emitted to the outside of the cell. As a result, the discharge cells adjust the period during which the discharge is maintained to implement gray scale, and the PDP in which the discharge cells are arranged in a matrix form displays an image.

5 is a diagram illustrating a PDP driving method according to an exemplary embodiment of the present invention and is a driving waveform diagram supplied for an arbitrary subfield period.

During the reset period RPD, the first and second reset pulses RPy and RPa are simultaneously supplied to the scan electrode 44 and the auxiliary scan electrode 46. Due to the first and second reset pulses RPy and RPa, reset discharges are generated in all discharge cells, and wall charges such that self discharge discharges do not cause erroneous discharges remain. In detail, the first reset pulse RPy supplied to the scan electrode 44 is supplied in the form of a ramp wave having a rising period and a falling period. The second reset pulse RPa supplied to the auxiliary scan electrode 46 is supplied in the form of a ramp wave having a rising period. Here, applying a voltage of zero potential to the auxiliary scan electrode 46 when the falling ramp waveform is supplied to the scan electrode 44 is compared with the distance between the scan electrode 44 and the sustain electrode 42. This is to prevent the wall charge amount from being formed differently even when the scan electrode 44 and the auxiliary scan electrode 46 have the same voltage polarity because the gap between the 46 and the scan electrode 44 is small. Due to the first and second reset pulses RPy and RPa, a reset discharge having a large emission size is not generated in the rising period, so that the dielectric layers around the sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46 are formed. 20, wall charges are formed. Subsequently, during the falling period of the first reset pulse RPy, a positive voltage (Vs) is applied to the sustain electrode 42 to thereby maintain the sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46. By inverting the polarity of, the wall charge is partially reduced to remain.

In the address period APD, the negative scanning pulse SP is supplied to the scanning electrode 44 in the line sequence, and the positive data pulse DP is supplied to the data electrode 26. Allow selective write discharge to occur. In this case, the auxiliary scan electrode 46 is synchronized with the scan pulse SP and a relatively small width, i.e., 1 μs, of the auxiliary pulse AP is supplied to the auxiliary scan electrode 46 to immediately before the selective write discharge. A secondary discharge is generated between the 44 so that priming charged particles are generated in the discharge space. These priming charged particles subsequently aid in selective write discharge generated between the data electrode 26 and the scan electrode 44. In other words, the filling charged particles compensate for the wall charges formed during the reset period decreasing with time and the wall charge amount is changed so that selective write discharge is generated under the same discharge condition. As a result, it is possible to perform stable and uniform selective writing. In general, the pulse widths of the scan pulse SP and the data pulse DP are about 2.4 [mu] s, and the application time of the scan pulse and the data pulse is about 1 [mu] s for the discharge preparation period. ) Is supplied at the same time as the data pulse DP and the scan pulse SP, but the secondary discharge occurs first and then the selective write discharge occurs. Sufficient wall charges are formed in the discharge cells in which such selective write discharge has occurred, and are maintained for a period during which other discharge cells are addressed.

In the sustain period SPD, trigger pulses TPy and TPa are supplied to the scan electrode 44 and the auxiliary scan electrode 46. The trigger pulses TPy and TPa cause sustain discharge between the sustain electrode 42 and the scan electrode 44 and the auxiliary scan electrode 46 of the discharge cells in which the wall charges are sufficiently formed. Subsequently, sustain pulses SUSPz, SUSPy, and SUSPa having a pulse width smaller than the trigger pulses TPy and TPa are alternately supplied to the sustain electrode 42, the scan electrode 44, and the auxiliary scan electrode 46. Allow maintenance discharge to be maintained. The auxiliary scan electrode 46 is synchronized with the scan electrode 44 and supplied with a sustain pulse SUSPa having a relatively low voltage to be used as a bus electrode of the scan electrode 44 during the sustain discharge. In the erase period EPD subsequent to the sustain period SPD, the erase pulse EP is supplied to the sustain electrode 42 to stop the discharge. The erasing pulse EP has a ramp wave shape in which the light emission size is small during the erasing discharge, and has a short pulse width for erasing the discharge. The charged particles are erased by the short erase discharge by the erase pulse EP to stop the discharge.

As described above, in the PDP and its driving method according to the present invention, the selective write discharge conditions in the respective discharge cells are the same as the auxiliary discharge using the auxiliary electrode, thereby making it possible to stabilize the selective write. Accordingly, the image quality can be improved as a result of preventing the image quality deterioration due to the time difference of the conventional selective writing.

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.

Claims (6)

In the plasma display panel including a plurality of discharge cells, the electrode group included in each of the discharge cells, A sustain electrode and a scan electrode formed side by side on the first substrate for sustain discharge; An address electrode orthogonally disposed on the second substrate for selective write discharge with the scan electrode; And an auxiliary scan electrode formed on the first substrate in parallel with the sustain electrode and the scan electrode to generate a priming discharge just before the selective write discharge. The method of claim 1, And the auxiliary scan electrode is a metal electrode formed adjacent to the scan electrode than the sustain electrode. The method of claim 1, Wherein the scan electrode has an electrode width smaller than that of the sustain electrode, and the auxiliary scan electrode has an electrode width smaller than that of the scan electrode. The method of claim 1, And the sustain electrode, the scan electrode, and the auxiliary scan electrode are disposed symmetrically with discharge cells vertically adjacent to each other. In a driving method of a plasma display panel having a plurality of discharge cells, Each of the discharge cells includes a sustain electrode, a scan electrode, an auxiliary scan electrode, and an address electrode, Initializing the discharge cells at the same time by causing a reset discharge; Causing a selective write discharge to occur between the scan electrode and the data electrode immediately after the auxiliary discharge occurs between the scan electrode and the auxiliary scan electrode; And maintaining a discharge in the discharge cells in which the selective write discharge has been generated. The method of claim 5, And an auxiliary pulse for the auxiliary discharge is supplied to the auxiliary scan electrode just before the selective write discharge is generated.

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