KR100593067B1 - Radio Frequency Plasma Display Panel - Google Patents

Abstract

The present invention relates to a high frequency plasma display panel. The high frequency plasma display panel of the present invention comprises: a high frequency electrode unit for supplying a high frequency signal to a plurality of discharge cells in common; A transparent electrode unit formed in each of the discharge cells; And a resistor connecting the high frequency electrode portion and the transparent electrode portion.

In such a high frequency plasma display panel, mutual interference between adjacent cells is prevented at the time of discharge, thereby enabling cell-based discharge control.

High frequency, plasma, display, panel, transparent electrode

Description

High Frequency Plasma Display Panel

1A is a plan view showing a lower plate of a high frequency plasma display panel according to the prior art;

FIG. 1B is a longitudinal sectional view of the lower plate shown in FIG. 1A; FIG.

Figure 2a is a plan view showing a top plate of a high frequency plasma display panel according to the prior art.

FIG. 2B is a longitudinal sectional view of the top plate shown in FIG. 2A; FIG.

3 is a view showing the overall electrode arrangement structure of the high frequency plasma display panel.

4 is a block diagram showing a driving device of a high frequency plasma display panel.

5 is a plan view illustrating a top plate of a high frequency plasma display panel according to an exemplary embodiment of the present invention.

6 is a voltage waveform diagram for driving a high frequency plasma display panel according to an exemplary embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

20: lower substrate 22: ground plate

24: first separation layer 26: address electrode

28: second separation layer 30: scanning electrode

32: dielectric layer 34: protective film

36: partition 38: discharge area

40,82: upper substrate 42,90: high frequency electrode

44: upper dielectric layer 46,86: discharge cell

48 phosphor 60 plasma display panel

62: address signal generator 64: scan signal generator

66: high frequency generation unit 68: low pass filter

70: capacitor 80: transparent electrode (ITO electrode)

84: vertical bulkhead 88: resistance

92: transverse bulkhead

The present invention relates to a high frequency plasma display panel, and more particularly, to a high frequency plasma display panel capable of controlling high frequency discharge on a cell basis.

A plasma display panel (hereinafter referred to as "PDP") is a display device in which ultraviolet light generated by gas discharge excites a phosphor to generate visible light from the phosphor. PDP has the advantages of being thin, light, high-definition large screen, and wider viewing angle than the cathode ray tube (CRT), which has been the dominant display device. In the PDP, by adjusting the number of sustain discharges, a gradation of brightness necessary for displaying an image, that is, gray scale, is realized. In the actual AC drive type PDP, in order to perform sustain discharge, a spherical pulse of usually 10 Hz to 100 Hz is periodically applied to the discharge sustaining electrode. In AC-driven PDP, the discharge is generated only once at a very short moment for one spherical pulse, and most of the discharge time is consumed in the step of forming wall charge and preparing for the next discharge, thereby lowering the discharge efficiency. In order to solve this problem, a PDP discharged by high frequency (hereinafter referred to as a "high frequency discharge PDP") has been proposed. In the high frequency discharge PDP, electrons vibrating by high frequency pulses ionize the discharge gas continuously so that the continuous discharge is performed for most of the discharge time.

1A and 1B are a plan view and a longitudinal sectional view showing a bottom plate structure of a high frequency discharge PDP according to the prior art, respectively. 1A to 1B, a lower plate of the high frequency discharge PDP may include a ground plate 22, a first separation layer 24, an address electrode 26, and a second layer stacked on the lower substrate 20. The separation layer 28, the scan electrode 30, the dielectric layer 32, the MgO passivation layer 34, and the partition 36 are formed vertically on the passivation layer 34. The scan electrodes 30 are arranged side by side in the longitudinal direction on the lower plate, and the address electrodes 26 vertically cross the scan electrodes 30. Each of the discharge cells 46 formed at the intersection of the scan electrode 30 and the address electrode 26 is separated by a partition 36. The ground plate 22 is used as a ground electrode for setting the base potential of the high frequency signal. The first separation layer 24 is an insulator for electrically insulating between the address electrode 26 and the ground plate 22. Similarly, the second separation layer 28 is also an insulator for electrically insulating between the address electrode 26 and the scan electrode 30. The second separation layer 28 also provides a space for forming wall charges during the address discharge between the scan electrode 30 and the address electrode 26. The dielectric layer 32 accumulates wall charges during sustain discharge. In addition, the dielectric layer 32 protects the scan electrode 30 during discharge. The MgO protective film 34 protects the dielectric layer 32 and the lower plate from sputtering during sustain discharge. On the partition 36 and the protective film 34, a phosphor 48 that emits visible light is applied. In the discharge region 38 formed between the partition walls, discharge gas excited during discharge is injected.

2A and 2B are a plan view and a longitudinal sectional view showing the top plate structure of the high frequency discharge PDP, respectively. 2A to 2B, the upper plate of the high frequency discharge PDP includes a high frequency electrode 42 formed in a lengthwise direction on a rear surface of the upper substrate 40, and an upper dielectric layer 44 entirely coated on the rear surface of the upper substrate 40. ). The high frequency electrode 42 is formed parallel to the scan electrode 30 at a point opposite to the scan electrode 30. The high frequency electrode 42 applies a high frequency signal during sustain discharge. The upper dielectric layer 44 protects the high frequency electrode 42 and accumulates wall charges during sustain discharge.

3 is a view showing the overall electrode arrangement structure of the high frequency discharge PDP. Referring to FIG. 3, the scan electrode and the high frequency electrode lines are arranged in a direction perpendicular to the address electrode lines arranged in the vertical direction. Discharge cells are provided at intersections of the address electrode lines, the scan electrode, and the high frequency electrode lines. The high frequency electrodes are common electrodes commonly connected to a high frequency signal source not shown in the figure.

Briefly describing the discharge process of the high frequency discharge PDP, when an AC signal is applied between the address electrode 26 and the scan electrode 30, an address discharge occurs. Charged particles are generated in the discharge region 38 due to the address discharge, and wall charges are formed in the second separation layer 28. The wall charge lowers the discharge voltage during sustain discharge. Then, when a high frequency signal is supplied to the high frequency electrode 42, the charged particles vibrate in the discharge region 38. As a result, sustain discharge occurs continuously while the discharge gas in the discharge region 38 is ionized continuously. Ultraviolet rays generated during the sustain discharge period excite the phosphor 48, and visible light is emitted from the phosphor 48 to implement an image of the PDP. As a high frequency signal, a square wave or a sine wave having a frequency of several tens of MHz to several hundred MHz is used.

As described above, the high frequency discharge PDP is driven by an AC signal for causing an address discharge and a high frequency signal for causing a sustain discharge. Therefore, the driving circuit of the high frequency discharge PDP consists of a circuit in which two signals having different frequencies are mixed.

4 is a block diagram showing a driving device of a high frequency discharge PDP. Referring to FIG. 4, the driving apparatus of the high frequency discharge PDP includes a PDP 60 having a high frequency electrode 42, a scan electrode 30, and an address electrode 26, and an address voltage V _Add to the address electrode 26. ) Is supplied to the address signal generator 62 for supplying the scan signal, the scan signal generator 64 for supplying the scan voltage V _Sc to the scan electrode 30, and the high frequency signal RF to the high frequency electrode 42. A low pass filter (Low-) connected between the high frequency generator 66 and the scan electrode 30 and the scan signal generator 64, and between the address electrode 26 and the address signal generator 62 for supplying the signal. Pass Filter (hereinafter referred to as " LPF &quot;) 68, and a capacitor 70 connected between the ground voltage source GND and the scan electrode 30.

When the AC signals V _Add and V _Sc are applied to the address electrode 26 and the scan electrode 30, addressing and ignition for each discharge cell is performed by an AC discharge between the address electrode 26 and the scan electrode 30. Is done. The ground terminal (point B) of the AC signals for address discharge is not a real ground, and the AC signals are supplied to the address electrode 26 and the scan electrode 30 in a floating state. The actual ground is connected to the high frequency generator 66. Subsequently, sustain discharge by the high frequency signal RF occurs following the ignition of the discharge cell. At this time, as shown in FIG. 4, the circuit is designed such that the ground of the high frequency signal is connected to the scan electrode 30 (A point) in order to provide the counter electrode of the high frequency electrode 42 during the sustain discharge. The scan electrode 30 applies the scan voltage V _Sc at the address discharge and also serves as a counter electrode of the high frequency electrode 42 at the sustain discharge. The capacitor 70 is used for the purpose of passing the high frequency signal RF during sustain discharge. The high frequency signal induced by the scan electrode 30 during the sustain discharge is blocked by the high frequency prevention LPF 68 so as not to affect the scan signal generator 64. On the contrary, since the scan signal at the time of address discharge has a lower frequency than the high frequency signal, the scan signal passes through the LPF 68 and is supplied to the respective scan electrode 30 lines. The LPF 68 is implemented as an inductor having an appropriate impedance value according to two frequencies of an AC signal and a high frequency signal. The LPF 68 can be designed for the same purpose in the address electrode portion.

In the conventional high frequency discharge PDP, it is impossible to supply a high frequency signal source that causes sustain discharge separately for each discharge cell. Accordingly, the high frequency electrodes are commonly connected to the high frequency signal source to supply the high frequency signals to all the discharge cells. Switching for selecting a cell for sustain discharge is performed in the address discharge process. In this case, the discharge voltage applied to one cell may affect another adjacent cell through the common high frequency electrode. That is, a problem occurs that causes discharge to other unwanted cells by crosstalk through a high frequency electrode. In addition, even in a method of erasing charged particles or ions by applying a strong electric field (or a reset signal) to a discharge cell in which high frequency discharge is sustained, the common high frequency electrode may be affected to disturb the high frequency signal source. This results in a problem that the erasing operation in one cell affects all cells, resulting in the inability to address the source. In conclusion, the conventional cell structure has a disadvantage in that it is inadequate to be applied to an image display apparatus in which a cell on and a cell on a screen exist at the same time because it is difficult to control discharge per cell.

Accordingly, an object of the present invention is to provide a high frequency plasma display panel capable of controlling discharge on a cell basis.

In order to achieve the above object, the high frequency plasma display panel according to the present invention includes a high frequency electrode unit for supplying a high frequency signal to a plurality of discharge cells in common; A transparent electrode unit formed in each of the discharge cells; And a resistor connecting the high frequency electrode portion and the transparent electrode portion.
According to such a feature, the high frequency electrode part is formed of an electrode line to apply a high frequency signal to a discharge cell line formed on the same line of the panel in common, and the electrode line is formed at a position other than the discharge space between each discharge cell line. do.
According to this feature, the electrode line is formed on the upper substrate so as to face the position where the partition wall between each discharge cell line is formed.
According to this feature, the transparent electrode portions are formed separately from each other on the discharge cells.
According to this feature, the resistor connects the individual transparent electrodes formed for each discharge cell of the discharge cell line with each high frequency electrode portion.
According to this feature, the resistance value of the resistor is selected as a value for preventing the reverse current from the transparent electrode portion from being induced into the high frequency electrode portion.

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 with reference to FIGS. 5 to 6.

5 is a plan view of an upper plate illustrating an electrode structure of a high frequency discharge PDP according to an embodiment of the present invention. Referring to FIG. 5, the high frequency electrode 90 is formed as an electrode line to supply a high frequency signal to all of the discharge cells in the discharge cell line corresponding to the row line of the panel. These high frequency electrode 90 lines are formed between each discharge cell line. That is, it is formed at the point where the transverse partition wall 92 on the rear surface of the upper substrate 82 is located. The high frequency electrode 90 is parallel to the scan electrode formed on the lower plate and is perpendicular to the address electrode. A transparent electrode (ITO electrode) 80 is widely formed on the rear surface of the upper substrate 82 on which the discharge cells 86 are located. The transparent electrodes 80 are formed separately in correspondence with the respective discharge cells 86. The transparent electrode 80 is connected to the high frequency electrode 90 by a resistor 88. The resistor 88 is formed at the point where the vertical bulkhead 84 on the rear surface of the upper substrate 82 is located.

The high frequency electrode 90 is used as a bus electrode and is a metal electrode having a relatively low resistance value. In the electrode structure according to the present invention, the high frequency electrode 90 is not formed across each of the discharge cells, but instead, the transparent electrode 80 is formed on the discharge cells 86, thereby sufficiently widening the electrode area. The size of the resistor 88 connecting the transparent electrode 80 and the high frequency electrode 90 is about several tens of micrometers to several micrometers.

The high frequency discharge PDP of the present invention is completed by joining the upper plate having the electrode structure as shown in FIG. 5 and the lower plate as shown in FIG. 1A. As a driving device for driving the high frequency discharge PDP of the present invention, a driving device as shown in FIG. 4 may be used.

FIG. 6 illustrates a driving method for driving a high frequency discharge PDP according to an exemplary embodiment of the present invention. The voltage waveform applied to the electrodes of the PDP during an arbitrary subfield by the driving apparatus shown in FIG. 4 is illustrated. It is shown.

Referring to FIG. 6, an arbitrary subfield is divided into an addressing period, a triggering period, a sustain discharge period, and a reset period. The addressing period is a period for selecting the discharge cells to be sustain discharged. In the addressing period, an address voltage V _Add and a scan voltage V _Sc are applied to the address electrode and the scan electrode of the PDP, respectively, and address discharge is performed in each discharge cell 86. A positive voltage (V _m ) is applied to the address signal and a negative voltage (V _dd ) is simultaneously applied to the scan signal. The discharge voltage at the address discharge becomes a high voltage corresponding to the potential difference between the positive voltage V _m and the negative voltage V _dd . Accordingly, wall charges are formed in the separation layer between the scan electrode and the address electrode of the discharge cell 86. At this time, the address discharge generated in one discharge cell does not affect the discharge of another adjacent cell. The common high frequency electrode 90, which is used as a bus electrode and supplies a high frequency signal to all the discharge cells, is connected by a resistor having a high value to the transparent electrode 80 formed separately from each discharge cell 86. This resistance serves to prevent reverse current from being induced from the transparent electrode 80 to the common high frequency electrode 90. Therefore, since address discharge generated in one discharge cell 86 does not affect the common high frequency electrode 90, mutual interference in which adjacent cells are erroneously discharged by a high frequency signal is prevented.

Even after a high-frequency signal is applied to the high-frequency electrode 90 after the address discharge, the level of the high-frequency signal is not large enough to cause a discharge in the addressed discharge cell 86, so that sustain discharge cannot be caused by itself. Accordingly, when the address discharge is completed, a triggering signal for inducing full high frequency sustain discharge is applied. In the triggering period, the positive voltage (V _s ) is sequentially applied to the address electrode and the scan electrode. On the other hand, the amount of wall charges formed for each discharge cell during address discharge has a non-uniform distribution due to the difference in discharge time points during the addressing period. Triggering also plays a role of making the amount of wall charges formed in the selected cells during the address discharge uniform so that a stable and uniform sustain discharge occurs when a high frequency signal is applied. Even during a triggering period, mutual interference between adjacent cells is prevented by the effect of a resistance connecting the transparent electrode 80 and the common high frequency electrode 90. Thus, discharge control in units of cells by addressing and triggering is possible.

When the high frequency discharge is started by triggering, sustain discharge occurs in the discharge cells addressed by the high frequency signals supplied to the respective discharge cells 86 through the common high frequency electrode 90. Since discharge start is performed by triggering, it is possible to control high frequency sustain discharge even with a low voltage. The charged particles in the discharge region vibrate by the high frequency signal applied to the high frequency electrode 90 during the sustain discharge. In this process, ultraviolet rays generated when the discharge gas in the discharge region is excited and fall to the ground state excite the phosphor coated in the discharge region. In the excited phosphor, visible light is generated, and the generated red, green, and blue visible light are combined to implement an image of the PDP. In this case, the brightness of each subfield varies according to the number of sustain discharges, that is, the sustain discharge period, and a plurality of subfields having different brightnesses are combined to implement gradation for one frame.

The reset period is a period for ending the discharge. In the reset period, sustain discharge is erased by applying the same positive voltage to the address electrode and the scan electrode to dissipate the space charge in the discharge region. Applying a positive (+) voltage to dissipate space charges is easier to move electrons with less kinetic energy and faster response time. Even in this case, since the high frequency electrode 90 is connected to the transparent electrode 80 of the discharge cell 86 by a high value of resistance, the high frequency electrode 90 is applied to a high voltage applied to a scan electrode or an address electrode or a high voltage applied for discharge erasing. Will not be affected. As a result, even when the discharge is erased, cross-talk which affects the discharge of adjacent cells does not occur, and discharge control in units of cells can be performed.

As described above, the high frequency plasma display panel according to the present invention has an advantage that the discharge can be controlled in units of cells by preventing mutual interference between the discharge cells. By forming the transparent electrode wide on the discharge cell, the electrode area for sustain discharge can be expanded to generate a uniform and strong high frequency discharge. Since the high frequency discharge is started by triggering before the sustain discharge, a low power discharge drive capable of sustaining the sustain discharge as a high frequency signal of low voltage becomes possible.

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)

A high frequency electrode unit for supplying a high frequency signal to a plurality of discharge cells in common; A transparent electrode unit formed in each of the discharge cells; And And a resistor for connecting the high frequency electrode portion and the transparent electrode portion. The method of claim 1, The high frequency electrode part is formed as an electrode line to apply a high frequency signal in common to the discharge cell line formed on the same line of the panel, The electrode line is a high frequency plasma display panel, characterized in that formed in a position other than the discharge space between each discharge cell line. The method of claim 2, And the electrode line is formed on the upper substrate so as to face a position where a partition wall between each discharge cell line is formed. The method of claim 1, The transparent electrode unit is a high frequency plasma display panel, characterized in that formed separately from each other on the discharge cells. The method of claim 1, And the resistor connects the individual transparent electrodes formed for each discharge cell of the discharge cell line with each of the high frequency electrode parts. The method of claim 1, The resistance value of the resistor is selected as a value for preventing the reverse current from the transparent electrode portion is induced to the high frequency electrode portion.

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