KR100255668B1 - A method for driving a gas discharge apparatus - Google Patents

Abstract

PURPOSE: A method for operating an electric discharge device is provided to obtain a sufficient operation margin by suppressing the increase in the electric discharge voltage of the electric discharge device. CONSTITUTION: The electric discharge device includes first and second electrodes(2,3) for generating maintaining discharges by alternatively applying electric discharge maintaining pulse(16a,16b), and the third electrode(5) for generating an address electric discharge together with the first electrode(2) or the second electrode(3) by receiving the electric discharge pulse. The electric discharge device is formed as a matrix shape so that it is correspondent to electric discharge space. The method for operating the electric discharge device comprises the step of applying a space charge controlling pulse to the third electrode(5) in order to overlay the applying period of the electric discharge maintaining pulses(16a,16b) with the applying period of the space charge controlling pulse(23).

Description

A method for driving a gas discharge apparatus

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of driving a discharge device, and more particularly, to an improvement in the discharge process of a discharge device represented by a plasma display panel.

A discharge device driven by a pulse voltage is a device having at least one pair of electrodes, and generating a discharge by applying a pulse voltage to at least one of the electrodes. Typical examples include a discharge lamp such as a fluorescent lamp or a backlight of a liquid crystal display device, a gas laser generator, an O ₃ generator for removing sulfur dioxide, and a plasma display panel. Among them, a typical discharge lamp will be described with reference to a back lighter of a liquid crystal display (LCD) and a plasma display panel representative of a discharge display device.

First, as illustrated in FIGS. 1A and 1B, the backlight of the liquid crystal display device discharges an internal space formed by the front substrate 1, the rear substrate 6, and the partition 8 that face each other. A pair of electrodes (2, 3) formed side by side at the edge of the discharge space facing surface of the rear substrate 6 and the conductive plate (5) formed over the entire surface of the discharge space facing surface of the front substrate (1). It is structured.

Next, the plasma display panel is generally classified into a DC type and an AC type. The DC plasma display panel has a structure in which all the electrodes are exposed to the discharge space, and thus the charge can be directly transferred between the electrodes corresponding to each other. The AC plasma display panel includes at least one of the electrodes corresponding to each other. One of the electrodes is surrounded by a dielectric and thus has a structure in which direct charge flow cannot occur between the corresponding electrodes. That is, in the DC type plasma display panel, as illustrated in FIG. 2A, the scan electrode 2 formed on the front glass substrate 1 corresponding to each other and the address electrode 5 formed on the back glass substrate 6 have a discharge space. Directly exposed to (4), direct charge transfer occurs between the two electrodes, and in the AC plasma display panel, as shown in FIG. 2B, the scan electrode 2 and the common electrode 3 are formed of a dielectric layer ( Surrounded by 7), no direct charge transfer can take place between the scan electrode 2 and the address electrode 5 or the scan electrode 2 and the common electrode 3, which correspond to each other electrically.

The driving method of the plasma display panel having such a structure is largely divided into the DC driving method and the AC driving method depending on whether the polarity of the voltage to be applied to maintain the discharge changes with time. A DC driving method or an AC driving method may be applied to the DC plasma display panel, and only an AC driving method may be applied to the AC plasma display panel.

FIG. 2A shows a DC type counter discharge structure of the plasma display panel, and FIG. 2B shows an AC type surface discharge structure. As shown, the discharge space 4 is formed in the opposing surface of the front glass substrate 1 and the back glass substrate 6. In the DC plasma display panel, the scan electrode 2 (anode) and the address electrode 5 (cathode) are directly exposed to the discharge space 4 so that the flow of electrons supplied from the address electrode 5 (cathode) maintains the discharge. It is a major energy source. In the AC plasma display panel, the scan electrode 2 and the common electrode 3 for maintaining the discharge are electrically separated from the discharge space because they are inside the dielectric layer 7. In this case, the discharge is maintained by the well-known wall charge effect. An example of such an AC type surface discharge structure PDP is illustrated in US Pat. No. 4,833,463 to AT & T.

In addition, the plasma display panel is classified into two types, a counter discharge structure and a surface discharge structure, according to a method of configuring electrodes for generating a discharge. These structures are divided into two-electrode structures, three-electrode structures, etc. in order to easily implement the discharge phenomenon. FIG. 2C shows a counter discharge structure, and FIG. 2D shows a surface discharge structure. In the counter discharge structure, an address discharge for selecting a pixel and a sustain discharge for holding the discharge are generated between the scan electrode 2 (anode) and the address electrode 5 (cathode) in the discharge space constituted by the partition wall 8. In the surface discharge structure, an address discharge for selecting a pixel is generated between the address electrode 5 and the scan electrode 2 that face each other in the discharge space formed by the partition wall 8, and then the scan electrode 2 and the common electrode are generated. A sustain discharge for maintaining the discharge occurs between (3). The partition wall 8 blocks the light generated during the discharge, together with the function of forming the discharge space, to prevent adverse effects on the neighboring pixels.

A plurality of unit cells as described above are formed on a single substrate, and a fluorescent material 9 is coated on each unit cell to form one pixel. These pixels gather to form a plasma display panel as shown in FIG. 3. Currently commercially available plasma display panels generate a discharge in each pixel, and the ultraviolet light generated by the discharge excites the fluorescent material 9 coated on the inner wall of the pixel to realize a desired color.

In order to perform the plasma display panel as a color image display, a gray scale is implemented. Currently, a gray scale implementation method of time division driving by dividing one field into a plurality of auxiliary fields is used. FIG. 4 is an explanatory diagram for explaining a gray scale implementation method of an AC plasma display panel applied to a product as a known technique. As shown, the gray scale display method of the AC plasma display panel adopts a method of time-dividing and driving one field into four auxiliary fields. Here, each auxiliary field is composed of an address period 9 and a discharge sustain period 10. The four auxiliary fields can display 2 ⁴ = 16 gray scales. That is, since the ratio of the discharge sustain periods of the first to fourth auxiliary fields is 1: 2: 4: 8, 0, 1 (1T), 2 (2T), 3 (1T + 2T), and 4 (4T), respectively. , 5 (1T + 4T), 6 (2T + 4T), 7 (1T + 2T + 4T), 8 (8T), 9 (1T + 8T), 10 (2T + 8T), 11 (3T + 8T), 16 gradations are displayed by configuring discharge sustain periods of 12 (4T + 8T), 13 (1T + 4T + 8T), 14 (2T + 4T + 8T), and 15 (1T + 2T + 4T + 8T). For example, only the second subfield 2T and the third subfield 4T need to be addressed so that the gray level 6 is displayed in an arbitrary pixel, and the first, second, third, and fourth subfields are displayed to display the gray level 15. All must be addressed.

FIG. 5 is a waveform diagram of signals applied to a commercially available method of driving an AC plasma display panel, and shows timings of signals applied to the address electrode 5, the scan electrode 2, and the common electrode 3, respectively. The erasing period 14 generates a weak discharge for accurate gradation display and erases wall charges caused by the previous discharge, thereby smoothing the operation of the next auxiliary field. In the address period 12, a discharge occurs only at a selected place (pixel) of the entire screen of the plasma display panel by selective discharge by the write pulse 15 between the crossed address electrodes 5 and the scan electrodes 2. To display the image. That is, the discharge of the pixels is triggered as the electrical signalized image information. The discharge sustain period 13 is a period in which image information is implemented by holding the discharge triggered by the addressed pixel on the actual screen as a continuous discharge sustain pulse 16.

Plasma display panels have problems such as discharge structure and driving method, and have low luminous efficiency and low luminance, and because of the use of discharge, the driving voltage is relatively higher than other display devices, and thus the driving voltage drop problem and high voltage driving circuit There is a problem in the development of the device. In addition, there is a problem of deterioration of visibility caused by virtual contour of moving picture resulting from gray scale by time division.

In the presently commercially available plasma display panel, since the method of driving the address discharge period and the sustain discharge period separately is applied, the display discharge by the sustain discharge can be assigned only 30% or less of one frame period. Therefore, the luminance is remarkably low, which has been a big limitation for general display devices. In addition, when applied to high definition (HD) display, the display discharge period is lowered to about half of the current level, thereby further reducing luminance. In order to improve the luminance performance, a method of performing simultaneous full-page address discharge and sustain discharge has been studied. Even when a driving method for separating address discharge and sustain discharge is applied, the frequency of the discharge sustain pulse is increased and the discharge sustain pulse is increased. By narrowing the width, we devised a method of putting a relatively large number of pulse trains in one subfield. In the case of increasing the frequency of the discharge sustaining pulse, the discharge sustaining pulse trains are adjacent to each other in time, so that the space charge due to the discharge caused by the preceding pulse affects the discharge characteristics of the next discharge, resulting in unstable discharge. Have characteristics. In addition, when the width of the discharge sustain pulse is reduced, the time for converting the space charge generated immediately after the discharge into the wall charge becomes relatively short, resulting in an increase in the discharge sustain voltage. In addition, when address and sustain discharge are simultaneously performed, the number of scanning lines that can be actually implemented is limited by inserting an address pulse between the discharge sustain pulse and the discharge sustain pulse. Therefore, in order to overcome this, high speed driving such as double speed driving and triple speed driving should be performed. In this case, as described above, the discharge instability due to the frequency rise and the discharge holding voltage increase due to the reduction of the discharge holding pulse width are avoided. There is no number.

The light efficiency of the plasma display panel is very low compared to the light efficiency of light sources such as fluorescent lamps and metal halide lamps that use electric discharges, so that even at the present highest level, the light efficiency does not exceed 1.2 kW / W. In the plasma display panel, the use of a short pulse as the discharge sustain voltage in the discharge sustain period improves the luminous efficiency during driving. This is to apply a voltage applied to the discharge holding period as a narrow pulse to improve the efficiency by reducing the thermal and electrical losses in the normal discharge process. In this case, the space charge immediately after the discharge cannot be effectively used, and the wall charge conversion rate of the space charge becomes low, resulting in an increase in the discharge holding voltage.

6 is an explanatory diagram for explaining the discharge principle of the AC plasma display panel. When the discharge sustain pulse 16 having the discharge start voltage 19 is applied, an increase in the wall voltage 18 due to an increase in the wall charge amount and a decrease in the discharge voltage 17 are shown. In the case of a normal discharge, when a discharge occurs, a space charge is generated and begins to accumulate on the two discharge sustaining electrodes (scanning electrode and common electrode) as wall charges, and as a result, the potential difference between the two electrodes gradually decreases. When the voltage between the two electrodes becomes the discharge extinction voltage 20, the discharge disappears but the remaining space charges continue to accumulate between the two electrodes by an electric field in the discharge space. Thus, the space charge continues to be converted to wall charge until all of the space charge disappears or until the potential difference between the two electrodes disappears. Of course, in this case, the survival time of the electrons and ions are different due to physical differences such as mobility. In addition, the density of wall charges and surplus space charges accumulated by the electric field has a great influence on the next discharge. Since the voltage of the discharge sustain pulse is determined by the difference between the discharge start voltage and the wall voltage formed by the wall charge, the greater the amount of wall charge, the lower the voltage of the discharge sustain pulse. In addition, depending on the amount and density distribution of the surplus space charge also acts as an obstacle to the next discharge, the discharge may be unstable.

As the width of the discharge sustain pulse 16 becomes narrower, the space charge formation period 22 becomes very short, making it difficult to generate sufficient space charge, and thus no control of wall charge and space charge after discharge extinction is achieved. In this case, in order to sustain the discharge, the discharge start voltage 19 applied to the electrode must be very high, which has a defect that makes the discharge easily occur in the adjacent electrode. Thus, the operating margin becomes very small, making it very difficult to discharge only the selected (addressed) pixels. That is, the margin of pulse voltage for maintaining stable discharge tends to be small. In addition, this margin may be lost.

Patent US 4,833,463 of AT & T Corporation discloses applying a negative pulse (-V _TC ) following an address electrode driving signal (+ V _W / 2; hereinafter referred to as an "address pulse") during an address discharge period. This is to facilitate the movement of the wall charges (-) formed near the address electrodes of the upper plate toward one of the two electrodes of the discharge sustaining electrode (scanning electrode or common electrode) of the lower plate. This does not apply to all AC PDP products on the market. That is, during the address period, negative charges are accumulated in the upper electrode of the upper plate, positive charges are simultaneously stored in one of the discharge sustaining electrodes (scanning electrode or common electrode) of the lower plate, and the negative charge accumulated in the address electrode of the upper plate is discharged. In order to move to the other side of the electrode (scanning electrode or common electrode), a positive pulse (+ V _ts ) is applied to the other side of the discharge sustaining electrode (scanning electrode or common electrode) to the address electrode of the upper plate. It is an essential step to move the accumulated wall charge (-) to the lower plate, and the negative pulse is to help the movement of the wall charge. Currently, most surface-discharge AC-PDP companies omit the discharging step by moving the wall charge as in the above method, and simultaneously discharge the positive charge to the discharge sustaining electrode (scanning electrode or common electrode) of the lower plate through full-screen discharge after full screen dropping. In other words, it adopts a method of forming negative charges.

As described above, the negative pulse is applied only once in the address period to promote the movement of the wall charges, thereby improving the utilization efficiency of the space charges during the discharge sustain period which substantially contributes to image display. Accordingly, there is a problem in that the negative pulses do not contribute to the improvement of the luminance or the discharge efficiency which is a problem in the plasma display device.

The present invention has been made to solve the above problems, and provides a method of driving a discharge device to ensure a sufficient operating margin by suppressing the rise of the discharge voltage of the discharge device driven by a high speed drive or a short pulse pulse. The purpose is.

1A and 1B are schematic perspective views of a backlight of a liquid crystal display device;

2A and 2B are vertical cross-sectional views of a DC type counter discharge structure and an AC type surface discharge structure plasma display panel, respectively;

2C and 2D are schematic perspective views of the plasma display panel of FIGS. 2A and 2B, respectively;

3 is a schematic exploded perspective view of a commercialized AC plasma display panel;

4 is an explanatory diagram for explaining a gray scale display method of the AC plasma display panel of FIG. 3;

5 is a waveform diagram of a conventional electrode driving signal for driving the AC plasma display panel of FIG.

6 is a graph for explaining the discharge principle of the AC plasma display panel of FIG.

7 is a waveform diagram showing an example of a discharge device drive signal according to the present invention in a discharge sustain period;

8A and 8B are diagrams illustrating a distribution state of space charges in an AC plasma display panel according to application of a driving signal of FIG. 7;

9 is a waveform diagram illustrating an electrode driving signal of an overall AC plasma display panel including the discharge device driving signal of FIG. 7;

10 to 57 are waveform diagrams illustrating another embodiment of the discharge device driving signal according to the present invention;

10 to 43 are waveform diagrams showing embodiments of a three-electrode surface discharge structure discharge device driving signal;

44 to 57 are waveform diagrams showing examples of a two-electrode opposing discharge structure discharge device drive signal;

58 is a detailed waveform diagram of electrode driving signals of a plasma display panel used in an experiment;

FIG. 59 is a graph showing Experimental Result I according to the electrode driving signal of FIG. 58. The time when the space charge control pulse is applied immediately after the discharge by the discharge sustain pulse is completed, the voltage of the space charge control pulse, and the voltage of the discharge sustain pulse. A graph showing the relationship between

60 is a graph showing Experimental Result II according to the electrode driving signal of FIG. 58;

A graph showing the voltage of the discharge sustain pulse according to the sustain discharge time by the discharge sustain pulse,

FIG. 61 is a graph showing Experimental Result III according to the electrode driving signal of FIG. 58, showing a voltage of a discharge sustain pulse according to a voltage of a space charge control pulse; FIG.

FIG. 62 is a graph illustrating Experimental Result IV according to the electrode driving signal of FIG. 58, illustrating a voltage of the discharge sustain pulse according to the width of the discharge sustain pulse when the pulse for space charge control is applied;

63A and 63B are graphs showing the experimental results V according to the electrode driving signal of FIG. 58, respectively. FIG. 63A is a graph showing the light output according to the discharge sustain pulse when the pulse for space charge control is not applied. FIG. 63B is a space charge. It is a graph showing the light output according to the discharge sustain pulse when the control pulse is applied.

<Description of the symbols for the main parts of the drawings>

1. Front glass substrate 2. Scanning electrode

3. Common electrode 4. Space charge

4'. 5. Discharge space 5. Address electrode

6. Back Glass Substrate 7. Dielectric Layer

8. Bulkhead 9. Phosphor

10. 1 field 11. Sub-field

12. Address period 13. Display discharge period

14. Erasing Period 15. Address Pulse

16. Discharge sustain pulse 16a. A large pulse

16b. Small pulse 17. Voltage between electrodes

18. Wall voltage 19. Discharge starting voltage

20. Discharge extinction voltage 21. Discharge period

22. Wall charge formation period 23. Space charge control pulse

24. Light output 25. Wall charge

26. Space charge (positive ion) 27. Space charge (electron)

28. Second Space Charge Control Pulse 29. Third Space Charge Control Pulse

30. Scanning Pulse

31. Period from immediately after discharge to application of space charge control pulse

32. Voltage of space charge control pulse 33. Width of discharge sustain pulse

34. Discharge sustain pulse voltage

In order to achieve the above object, a method of driving a discharge device according to the present invention includes at least one pair of electrodes, and generates discharge by applying a discharge address pulse and a discharge sustain pulse to at least one of the electrodes. A method of driving a discharge device, the method comprising: applying a space charge control pulse to at least one of the electrodes to overlap the application period of the discharge sustain pulse.

In the present invention, the space charge control pulse is applied to only one electrode of the pair of electrodes, and the discharge sustain pulses are alternately applied to the other electrode to which the space charge control pulse is not applied. Preferably, the space charge control pulse has the same polarity as the discharge sustain pulse, and furthermore, the discharge sustain pulses having opposite polarities are formed by attaching two pulses having different voltage values, respectively. It is also preferable to apply a small pulse of relatively small voltage later, and apply the space charge control pulse coinciding with the start point of the small pulse.

In addition, in the present invention, the space charge control pulse is applied to all of the pair of electrodes, the discharge sustain pulse of the same polarity is applied to the pair of electrodes alternately applied to each electrode, the space charge control pulse It is also preferably made of a pulse of the same polarity as the discharge sustain pulse and applied so as to overlap with the discharge sustain pulse applied to the other electrode in time between the discharge sustain pulse of each electrode.

Further, in the present invention, a third electrode other than the pair of electrodes is further provided, the space charge control pulse is applied to the third electrode, and the discharge sustain pulse is applied to one of the pair of electrodes. Only the discharge sustain pulses alternately have pulses having opposite polarities, and the space charge control pulses have the same polarity as the discharge sustain pulses. The other two pulses may be attached to each other, but a small pulse of relatively small voltage may be added after a large pulse of relatively large voltage, and the space charge control pulse may be applied coincident with the start of the small pulse.

Further, in the present invention, a third electrode other than the pair of electrodes is further provided, and the space charge control pulse is applied to the third electrode, and the discharge sustain pulses having the same polarity are applied to the pair of electrodes. Apply to each electrode alternately, and the space charge control pulse has the same polarity as the discharge sustain pulse, but the space charge control pulse starts to be applied prior to the application period of the discharge sustain pulse. After the application period ends, the application is terminated, or the space charge control pulse is started prior to the application period of the discharge sustain pulse so that the application ends within the application period of the discharge sustain pulse, or the space charge control pulse Application is started within the application period of the discharge sustain pulse and application is performed within the application period of the discharge sustain pulse. Or the application of the space charge control pulse starts to be applied within the application period of the discharge sustaining pulse so that the application is terminated after the application of the discharge sustaining pulse is finished, or the application time of the space charge control pulse is applied to the discharge sustaining pulse. It is also preferable that the discharge time is immediately after the discharge and the end of the space charge control pulse is a predetermined time after the discharge sustain pulse is finished.

In addition, in the present invention, the discharge sustain pulse is composed of two pulses of different voltage values, but a relatively small voltage followed by a small pulse of relatively small voltage, and the space charge control pulse is It is also preferable to apply the same coincidence with the start point of the small pulse. Furthermore, the pair of electrodes in parallel with each other corresponding to the space charge control pulses have a lower voltage level than the small pulse between the discharge sustain pulses. It is also preferable to further apply the second space charge control pulses whose polarity is opposite to the space charge control pulse.

Further, in the present invention, the space charge control pulse starts to be applied immediately after the discharge by the discharge sustain pulse, and when the absolute value of the voltage of the discharge sustain pulse is 0V to 200V, It is preferable that the absolute value is between 0V and 150V.

In addition, in the present invention, the space charge control pulse is applied to only one electrode of the pair of electrodes, and discharge sustain pulses having alternating pulses of opposite polarities are applied to the other electrode to which the space charge control pulse is not applied. Preferably, the space charge control pulse may have the same polarity in one-to-one correspondence with the discharge sustain pulse, and apply a discharge sustain pulse having the same polarity to each of the pair of electrodes, and alternately apply the discharge sustain pulse to each electrode. The charge control pulse is applied to all of the pair of electrodes, but is applied to the discharge sustain pulses of the same polarity as the discharge sustain pulses so as to overlap with the discharge sustain pulses applied to the other electrodes in time. It is also preferable.

In the present invention, a third space charge control pulse having a voltage level greater than the space charge control pulse is applied to at least one of the pair of electrodes to the third electrode, wherein one side of the pair of electrodes is applied. Discharge sustain pulses in which pulses of opposite polarities are alternately applied are applied to the other side, and the space charge control pulse having the same polarity as the discharge sustain pulse is applied to the other electrode, and the third corresponding to each of the discharge sustain pulses is applied. The space charge control pulses may have the same polarity as the discharge sustain pulse, or apply a discharge sustain pulse having the same polarity to the pair of electrodes in parallel, and alternately apply them to the two electrodes, and the other electrodes between the discharge sustain pulses. Same polarity or half as that of the discharge sustain pulse so as to overlap the application period of the discharge sustain pulse applied to Is applied to the space charge control of the pulse polarity, the third space-charge control of the pulse corresponding to a sustain discharge pulse applied to the two electrodes are preferably the same sustain pulse and the polarity of the discharge.

In the present invention, the space charge control pulse preferably has a voltage level within a range that does not generate magnetic flux discharge due to its own voltage.

In the present invention, the application time of the space charge control pulse is immediately after the end of the discharge by the discharge holding pulse or after a predetermined time has passed since the end of the discharge by the discharge holding pulse. Preferably, the width is within 3 μsec.

In addition, another method of driving the discharge device according to the present invention in order to achieve the above object, a pair of side-by-side first electrode and second electrode to generate a sustain discharge by alternately applying a discharge sustain pulse of the same polarity; And a third electrode crossing the side-by-side pair of electrodes and applying a discharge address pulse to generate an address discharge with at least one of the pair of electrodes so that the discharge electrodes correspond to the discharge spaces corresponding to each pixel one-to-one. A method of driving a discharge device which is formed in a matrix to cause discharge, the method comprising: applying a space charge control pulse to at least one of the electrodes to overlap the application period of the discharge sustain pulse; do.

In the present invention, the application of the space charge control pulse is started prior to the application period of the discharge maintenance pulse and the application is terminated after the application period of the discharge maintenance pulse is over, or the space charge control pulse of the discharge maintenance pulse The application is started before the application period and the application ends in the application period of the discharge sustain pulse, or the application of the space charge control pulse starts the application within the application period of the discharge sustain pulse and the application ends in the application period of the discharge sustain pulse. Alternatively, the application of the space charge control pulse is started within the application period of the discharge sustain pulse, and then the application is terminated after the application of the discharge sustain pulse ends. Particularly, the application time of the space charge control pulse is discharged by the discharge sustain pulse. Immediately after this, the end time of the space charge control pulse is the discharge holding After a predetermined time has elapsed after the end of the switch, or the application time of the space charge control pulse is immediately after the discharge by the discharge sustain pulse or after a predetermined time has passed from the end of the discharge by the discharge sustain pulse. The width of the space charge control pulse is preferably within 3 μsec.

In the present invention, the discharge sustain pulse is composed of two pulses of different voltage values, but a relatively small voltage followed by a small pulse of a relatively small voltage, and the space charge control pulse is the small pulse. It is also preferable to apply in coincidence with the start point of. Further, the parallel pair of electrodes corresponding to the space charge control pulses has a voltage level smaller than the small pulse between the discharge sustain pulses and the space charge. It is also preferable to further apply the second space charge control pulses whose polarity is opposite to the control pulse.

All.

In the present invention, immediately after the discharge by the discharge holding pulse, the space charge control pulse is started to be applied, and when the absolute value of the voltage of the discharge holding pulse is 0V to 200V, the absolute value of the voltage of the space charge control pulse. Is preferably between 0V and 150V.

In the present invention, the space charge control pulse is applied to the third electrode, and the discharge sustain pulse is applied to only one electrode of the pair of parallel electrodes, wherein the discharge sustain pulse alternately has pulses of opposite polarity. Preferably, the space charge control pulse has the same polarity in one-to-one correspondence with the discharge sustain pulse, and furthermore, the discharge sustain pulse is formed by attaching two pulses having different voltage values and relatively after the large pulse of a relatively large voltage. It is also preferable to apply a small voltage small pulse and apply the space charge control pulse coinciding with the start point of the small pulse.

In the present invention, the space charge control pulse is applied to the third electrode, and the discharge sustain pulse is applied to only one electrode of the pair of parallel electrodes, or is applied to the same pair of electrodes alternately in time. It is also made of a pulse of the polarity, the pulse for space charge control is preferably the same polarity as the discharge sustain pulse.

In the present invention, the space charge control pulse is applied to only one electrode of the pair of parallel electrodes, and a discharge sustain pulse having alternating pulses of opposite polarities is applied to the other electrode to which the space charge control pulse is not applied. The pulses for space charge control have the same polarity in one-to-one correspondence with the discharge sustain pulses, or apply pulses of the same polarity to the pair of electrodes, which are alternately applied to each electrode, and the pulses for space charge control alternately. It is also applied to all of the pair of electrodes, it is preferable to apply so as to overlap in time with the discharge sustain pulse applied to the other electrode between the discharge sustain pulse of each electrode in a pulse of the same polarity as the discharge sustain pulse, Furthermore, said space is at least one electrode of said pair of parallel electrodes It is also preferable to apply a third space charge control pulse having a voltage level larger than the charge control pulse.

In the present invention, the third space charge control pulse is applied to the third electrode, but a discharge sustain pulse in which pulses of opposite polarities are alternately applied to one side of the pair of parallel electrodes is applied, and the other electrode. The space charge control pulse having the same polarity as that of the discharge sustain pulse is applied, and the third space charge control pulse corresponding to each of the discharge sustain pulses has the same polarity as that of the discharge sustain pulse, or the parallel A discharge sustain pulse having the same polarity is applied to a pair of electrodes, but alternately applied to two electrodes, and the same polarity as the discharge sustain pulse so as to overlap the application period of the discharge sustain pulse applied to the other electrode between the discharge sustain pulses. Or a pulse for controlling space charge of opposite polarity is applied and sustains the discharge applied to the two electrodes. It is preferable that the third space charge control pulse corresponding to the pulse has the same polarity as the discharge sustain pulse.

In the present invention, it is also preferable that the space charge control pulse has a voltage level within a range that does not generate magnetic flux discharge due to its own voltage.

In addition, in order to achieve the above object, another method of driving the discharge device according to the present invention, the first electrode and the second electrode formed on the opposite surface of the substrate facing each other in the form of stripes in the direction crossing each other, respectively A method of driving a discharge device in which a discharge cell is formed in a matrix so as to correspond to discharge spaces corresponding to each pixel in a one-to-one manner, and a discharge sustain pulse is applied to at least one of the two electrodes to generate a sustain discharge. Applying a space charge control pulse to any one of the electrodes to overlap the application period of the;

In the present invention, the application of the space charge control pulse is started prior to the application period of the discharge maintenance pulse and the application is terminated after the application period of the discharge maintenance pulse is over, or the space charge control pulse of the discharge maintenance pulse The application is started before the application period and the application ends in the application period of the discharge sustain pulse, or the application of the space charge control pulse starts the application within the application period of the discharge sustain pulse and the application ends in the application period of the discharge sustain pulse. Alternatively, the space charge control pulse is preferably applied within the application period of the discharge sustain pulse so that the application ends after the application of the discharge sustain pulse.

In the present invention, the application time of the space charge control pulse is immediately after the end of the discharge by the discharge sustain pulse or after a predetermined time has passed from the end of the discharge by the discharge sustain pulse. It is also preferable that the width is within 3 µsec.

In the present invention, the discharge sustain pulse is composed of two pulses of different voltage values, but a relatively small voltage followed by a small pulse of a relatively small voltage, and the space charge control pulse is the small pulse. It is preferable to apply in accordance with the beginning of.

In the present invention, immediately after the discharge by the discharge holding pulse, the space charge control pulse is started to be applied, and when the absolute value of the voltage of the discharge holding pulse is 0V to 200V, the absolute value of the voltage of the space charge control pulse. Is preferably between 0V and 150V.

In the present invention, an address pulse is applied to the first electrodes, and a scan pulse corresponding to each one of the address pulses applied to each of the first electrodes is sequentially applied to the second electrodes, one by one. Afterwards, the discharge sustain pulse is periodically applied for a predetermined period, and the space charge control pulse is applied to overlap the discharge sustain pulse in time between the address pulses. It is also preferable that the polarity is the same or the opposite, wherein the discharge sustain pulse alternately has pulses of opposite polarity, and applies a space charge control pulse having the same polarity or the opposite one to the discharge sustain pulse to the first electrode. It is also preferable.

In the present invention, the space charge control pulse is preferably a pulse having a voltage within a range in which magnetic flux discharge due to its own voltage is not generated.

Hereinafter, a driving method of the discharge device according to the present invention will be described in detail with reference to the drawings.

According to the present invention, a space charge control pulse is applied to an address electrode during a discharge holding pulse applied to a discharge holding electrode during a discharge holding period of a discharge device, particularly a plasma display panel, driven by a pulse voltage. It is characterized by suppressing the rise and ensuring a sufficient operating margin. In explaining the application method of the pulse for space charge control, first, the driving method for the PDP of the three-electrode surface discharge structure will be described in detail, and then the driving method for the PDP of the two-electrode opposing discharge structure will be described. In the driving method of a general gas discharge device, the driving method of the three-electrode structure is the same as the driving method of the three-electrode surface discharge structure PDP, and thus the two-electrode structure driving method is combined with the driving method of the PDP of the three-electrode surface discharge structure. Explain.

7 is a waveform diagram of one embodiment (first embodiment) for implementing the method of the present invention, which is a waveform diagram of electrode driving signals applied to an AC type three-electrode surface discharge plasma display panel. As shown, the main characteristic of the sustain discharge driving is the space charge in accordance with the application period of the two discharge sustain pulses 16a and 16b respectively applied to the pair of electrodes 2 and 3 which are the main electrodes for generating the sustain discharge. The control pulse 23 is applied to the address electrode 5. That is, in the example of FIG. 7, the address electrode 5 is negatively connected from immediately after the occurrence of the respective sustain discharge 24 to just before the end of the discharge sustain pulse 16 in synchronism with the negative sustain sustain pulse for performing the sustain discharge. A space charge control pulse 23 having a voltage is applied to control the space charge in the discharge space. This increases the conversion rate of space charges to wall charges, which in turn increases the wall voltages, resulting in sustained discharges at lower voltages.

8A and 8B show a space charge distribution state appearing on an AC plasma display panel when a discharge sustain signal and a space charge control pulse as shown in FIG. 7 are applied. 8A shows a state immediately after the sustain discharge is completed between the scan electrode 2 and the common electrode 3. In this case, negative wall charges 25 are formed on the positive electrode during discharge, and positive wall charges 26 are formed on the negative electrode. The extra charged particles are distributed in the discharge space as space charges 27 and are accumulated as wall charges on each electrode depending on the distribution of the electric field. After the application of the discharge sustaining pulse is completed, the surplus space charge exists in the space in an arbitrary distribution, and over time, the disorder of the space charge 27 increases, and the space charge 27 disappears due to diffusion and recombination. . FIG. 8B shows the distribution of charge when the space charge control pulse 23 having a discharge start voltage lower than the discharge start voltage is applied to the address electrode 5 immediately after the discharge is completed between the scan electrode 2 and the common electrode 3. . In this case, the space charge 27 still remaining in the discharge space has kinetic energy due to the electric field formed by the space charge control pulses, so as to collide with the scan electrode 2 or the common electrode 3 to increase the wall charge amount. As a result, the wall voltage is increased to maintain the discharge by the relatively low discharge voltage. Since the space charge control pulse 23 has a low voltage, no new magnetic flux discharge occurs due to the application of the pulse voltage.

FIG. 9 is a waveform diagram illustrating an electrode driving signal of an overall AC plasma display panel including the discharge device driving signal of FIG. 7. FIG. 9 is an example of an electrode driving signal applied to realize a discharge device driving method according to the present invention. Indicates. The electrode drive signals of FIG. 7 are signals of a complete structure in which the electrode drive signal waveforms of the sustain discharge period of FIG. 6 are combined with the signal waveforms of the erase period 14 and the address period 15. As described above, the driving timing of the AC plasma display panel is usually an erasing period 14 for removing remaining charges, an address discharge period 12 for selecting an arbitrary pixel, and a sustain sustaining light emission. ) Period 13. Here, the space charge control pulse 23 is applied to the address electrode 5 in synchronization with the discharge sustain pulse 16 in the discharge sustain period 13. That is, in this embodiment, the space charge control pulse 23 is added to the address electrode 5 to drive the discharge device during the discharge sustain period 13, thereby controlling the space charge in the discharge space to lower the discharge start voltage. Thus, it is possible to maintain discharge at a lower voltage. To this end, the space charge control pulse 23 added to the address electrode 5 is applied with a negative voltage during the application period of the discharge sustain pulse 16a of the scan electrode 2 and the discharge sustain pulse 16b of the common electrode 3. A pulse (hereinafter referred to as " sub pulse ") is applied, and the period coincides with the two discharge sustain pulses 16a and 16b. By doing this, it becomes possible to control the space charge generated by the discharge generated by the two discharge sustain pulses.

As another embodiment of the present invention, there are the following methods of applying the space charge control pulse.

First, in order to control the sustain discharge itself, as shown in FIGS. 10 and 11, the discharge sustain pulse 16 is applied and the space charge control pulse 23 is applied and the discharge sustain pulse 16 ends. At the same time, the space charge control pulse 23 may be terminated. 12 and 13, the space charge control pulse 23 may be terminated before the discharge sustain pulse 16 ends. In addition, as shown in FIGS. 14 and 15, the space after the sustain discharge by the discharge sustain pulse 16 is used to control the wall charges accumulated in the X and Y electrodes using the width of the space charge control pulse 23. In some cases, the charge control pulse 23 is applied and the space charge control pulse 23 is terminated before the discharge sustain pulse 16 ends. As shown in FIGS. 16, 17, 18, and 19, in order to stably generate the sustain discharge, the space charge control pulse 23 may be applied before the sustain discharge occurs, thereby allowing the space charge to remain in the discharge space first. It may be controlled. 18 and 19, the wall charge accumulation amount can be controlled by making the end point of the space charge control pulse 23 earlier than the end point of the discharge sustain pulse 16. Also, as shown in FIGS. 16, 17, 20, and 21, the space charge control pulse 23 is terminated after the application of the discharge sustain pulse 16 ends, thereby remaining space disappeared by diffusion after the sustain discharge ends. Control the density of the charge. This remaining space charge acts to weaken the electric field in the discharge space formed by the discharge sustaining pulses 16 subsequently applied, thereby adversely affecting the instability or increasing the discharge voltage. By applying the space charge control pulse 23 extended in this period, it is possible to control the distribution of the remaining space charge so that the discharge is maintained more stable and at a lower voltage.

As another embodiment of the present invention, as shown in Figs. 22 and 23, the waveform of the discharge sustaining pulse 16 may be multistage. In other words, the large sustain pulse is combined by the large pulse 16a of the large voltage and the small pulse 16b of the small voltage. In this case, the discharge is generated in the large pulse 16a, and the small pulse 16b converts the space charge generated after the forced erase to the wall charge. In the case of the narrow pulse driving method for improving the light efficiency as described above, the light efficiency can be increased by forcibly canceling the discharge to prevent heat loss at the end of the discharge, but there is no electric field that converts the space charge to the wall charge after the forced cancellation. There was a defect that the discharge holding voltage became high and as a result, the operation margin was lost. However, by using the discharge sustain pulse of the multi-step waveform, the large pulse 16a of the multi-stage discharge sustain pulse has a function as a narrow pulse, and the small pulse 16b has a function of forcibly discharging the discharge and generating wall charge. You can do it. In this case, since the small pulse 16b cannot make an electric field sufficient to convert the space charge to the wall charge, the space charge control pulse 23 of the present invention is applied like the small pulse 16b to more efficiently control the space charge. Do it. 24 and 25 further extend this concept to match the small pulses 16b of the discharge sustain pulses 16a and 16b to one electrode to which the discharge sustain pulses 16 are not applied to have a constant voltage of opposite polarity. The second space charge control pulse 28 is applied. In this case, the widths and voltages of the pulses applied to the two discharge sustaining electrodes and the address electrodes can be adjusted, and thus an optimized electric field distribution can be formed in the discharge space. Since the optimized electric field distribution efficiently controls the space charges, the wall charges can be increased and the remaining space charges can be reduced. As a result, the discharge sustain voltage can be lowered and the stability of the discharges can be increased. In another embodiment, as shown in FIGS. 26 and 27, the positive and negative discharge sustain pulses 16 are alternately applied to one side of the discharge sustaining electrode, and the space charge control pulse 23 is maintained even when the other side maintains a constant voltage. ) Can be applied. That is, as shown in FIG. 26, the discharge sustain pulse 16 is applied to only one side of the two discharge sustain electrodes, but the discharge sustain pulse 16 is applied in such a manner that pulses having opposite polarities alternate with each other. The space charge control pulses 23 applied to the address electrodes 5 corresponding to the discharge sustain pulses 16 also alternately apply pulses of opposite polarities. This driving method is applied to the multi-stage discharge sustain pulses 16a and 16b as shown in FIGS. 22 and 23, and as shown in FIG. 27, positive and negative multi-stage pulses are applied to only one of the two discharge sustain electrodes. 16a, 16b) may be applied alternately. The multi-stage discharge sustain pulses 16a and 16b are pulses composed of multi-stage voltages made up of a combination of a large pulse 16a and a small pulse 16b.

As another embodiment, there is a method of placing a space charge control pulse 23 between the discharge sustain pulses 16 applied to the two discharge sustain electrodes 2 and 3. 28 and 29 show that when the discharge sustain pulses of the same polarity are alternately applied to the two discharge sustain electrodes 2 and 3, nothing is applied to the address electrode 5 and the space charge control pulse 23 is discharged. This is the case where it is applied between the sustain pulses 16. In this case, the space charge control pulses 23 applied to the discharge sustaining electrodes 2 and 3 corresponding to each other are constituted by pulses having the same polarity as the discharge sustaining pulses 16, but discharge sustaining pulses applied to the other discharge sustaining electrodes ( 16) to overlap with time. This method is effective in the case where it is difficult to implement the discharge sustain pulse 16 as a narrow pulse or when it is difficult to implement a multi-level pulse in order to obtain the light efficiency improvement effect by the narrow pulse described above. The display discharge is forcibly erased by adjusting the application time and the voltage, and then the space charge is controlled.

FIG. 30 shows that when discharge sustain pulses of opposite polarity are alternately applied to either one of the two discharge sustain electrodes 2 and 3, nothing is applied to the address electrode 5, and the space charge control pulse ( 23 is applied between the discharge sustain electrodes 2 to which the discharge sustain pulse 16 is not applied. In this case, the space charge control pulses 23 alternately apply pulses of opposite polarity so as to be composed of pulses having the same polarity as the discharge sustain pulse 16, but overlap each other with the discharge sustain pulse 16 in time. The driving method as shown in FIG. 31 is applied to the multi-level discharge sustaining pulses 16a and 16b. That is, when the multi-stage discharge sustaining pulses having opposite polarities are alternately applied to any one of the two discharge sustaining electrodes 2 and 3, the address electrode 5 is kept at a constant voltage without applying anything. This is a case where the space charge control pulse 23 is applied to the discharge sustain electrode 2 to which the discharge sustain pulse 16 is not applied in the application period of the multi-level discharge sustain pulses 16a and 16b. At this time, the space charge control pulses 23 are alternately applied to the pulses of opposite polarity so as to be composed of pulses of the same polarity as the polarity of the multi-level discharge sustaining pulses 16a and 16b, but the large pulse 16a of the large voltage and It is applied to be synchronized with the small pulse 16b of the multi-stage discharge sustaining pulses 16a and 16b made up of the combination of the small voltage small pulses 16b.

32 and 33 show a method of applying the polarity of the space charge control pulse 23 opposite to the polarity of the discharge sustain pulse 16 in the drive waveforms of FIGS. 30 and 31, respectively. In this driving method, it should be noted that the pulse 23 for space charge control is applied after the discharge by the discharge sustain pulse 16 is completed, and the electric field is sufficient to offset the electric field due to the wall charge generated by the discharge. It is preferable to limit the voltage of the space charge control pulse 23 to the voltage generated. That is, when the discharge holding pulse 16 is first applied to discharge and wall charge is formed, the space charge control pulse 23 is applied. However, the potential difference between the discharge holding pulse 16 and the space charge control pulse 23 at this time is applied. The voltage is not greater than the voltage enough to cancel the electric field due to wall charge than the discharge sustain pulse 16 voltage.

34 and 35 show an extension of the embodiment in which the address electrode 5 is maintained at a constant voltage (mainly 0 V), and the third electrode is connected to the address electrode 5 together with the discharge sustain pulse 16 and the space charge control pulse 23. Is a case where the space charge control pulse 29 is applied. Also in this case, as described above, by adjusting the voltage and width of the pulses applied to the two discharge sustaining electrodes 2, 3 and the address electrode 5, the wall charge amount can be increased and the stability of the discharge can be improved. FIG. 34 shows that the third space charge control pulse 29 consisting of negative pulses is applied to the address electrode 5 when the discharge sustain pulse 16 is a negative pulse, and the discharge sustain pulse 16 is not applied ( The positive space charge control pulses 23 are applied to the discharge discharge electrodes 2 and 3 on the opposite sides of each other, and FIG. 34 is applied to the address electrodes 5 when the discharge sustain pulses 16 are positive pulses. The third space charge control pulse 29 consisting of pulses is applied, and the negative space charge control pulses are applied to the opposite discharge holding electrodes 2 and 3 to which the discharge holding pulses 16 are not applied (is resting). 23) is applied. In this way, when the third space charge control pulse 29 is applied to the address electrode, the effect of lowering the discharge holding voltage as described above can be obtained.

As a further embodiment, the method as shown in Figs. 28 and 29 extends the space charge control pulses 23 between the discharge sustain pulses 16 applied to the two discharge sustain electrodes 2 and 3. The third method is to apply the third space charge control pulse 29 to the above method. That is, in the method as shown in Figs. 28 and 29, as shown in Figs. 36 and 37, the discharge sustain pulse 16 is applied to the address electrode 5 at the same time as the discharge sustain pulse 16 is applied. By applying the third space charge control pulse 29 of polarity, it is possible to optimize the electric field distribution formed by the three electrodes to increase the amount of conversion of the space charge to the wall charge and to increase the stability of the discharge. 36 and 37 show the space charge control pulses 23 applied to the discharge sustain pulses 16 having opposite polarities, respectively. In this case, the space charge control pulses 23 have the same polarity as the discharge sustain pulses 16, respectively. Is applied, and the third space charge control pulse 29 is also composed of pulses having the same polarity as that of the discharge sustain pulse 16.

Also in the driving method as shown in Figs. 30 and 31, the positive and negative discharge sustain pulses 16 and the multi-stage discharge sustain pulses 16a and 16b are alternately applied to one side of the discharge sustain electrode. As shown, the third space charge control pulse may be applied to the address electrode 5. In the case of FIG. 38, the third space charge control pulse 29 is configured by alternately applying pulses having opposite polarities, and is applied in the same polarity in synchronization with the space charge control pulse 23 and the discharge sustain pulse 16. In the case of Fig. 39, the third space charge control pulse 29 is configured by alternately applying pulses of opposite polarity, but is applied in the same polarity in synchronization with the small pulse 16b of the discharge sustaining pulse 16. In this manner, there is an effect that the voltage of the discharge sustain pulse 16 can be reduced to a minimum.

Thus, the driving method as shown in FIGS. 26-31 which keeps any one of three electrodes at a constant voltage (mainly 0V) can be applied as it is to the general gas discharge apparatus which has two electrodes. That is, assuming that the electrode to which a constant voltage is applied does not exist, the electrode driving signal applied to the remaining two electrodes may be applied to the gas discharge device having the two electrodes as it is. Here, since the two electrodes do not intersect with each other like the two electrodes of the PDP having the opposite discharge structure but are parallel to each other or opposite structures in almost the same area, the PDP driving signal of the three-electrode surface discharge structure as described above may be applied as it is. .

In the method shown in Fig. 38, the third space charge control pulse 29 is composed of pulses of the same polarity as shown in Figs. 40 and 41, so that the discharge can be obtained when the narrow pulse is applied or the multi-step pulse is applied. It is also possible to give a forced erase function.

As shown in FIGS. 42 and 43, the polarity of the first space charge control pulse 23 does not coincide with the polarity of the discharge sustain pulse 16 in the driving method of FIGS. 38 and 39 as described above. There is a method to apply. In the case of Fig. 42, the third space charge control pulse 29 and the discharge sustain pulse 16 are configured by alternately applying pulses of opposite polarity, but are synchronized with each other so as to be the same polarity, and the space charge control pulse 23 ) Is applied in synchronization with the third space charge control pulse 29 and the discharge sustain pulse 16 so as to be opposite polarities. In the case of Fig. 43, the third space charge control pulse 29 is applied in synchronization with the discharge sustain pulses 16a and 16b alternately applied with the pulses of the multi-level voltages having opposite polarities, but the same as the polarity of the discharge sustain pulses. Pulses of opposite polarity are alternately applied to each other, and the space charge control pulses 23 are applied at opposite polarities in synchronization with the small pulses 16b of the multi-stage discharge sustaining pulses 16a and 16b. In this way, the wall charge and the space charge can be appropriately controlled by reversing the polarity of the space charge control pulse 23 with the polarity of the discharge sustain pulse 16.

As another embodiment of the present invention, in the discharge device of the opposite discharge structure composed of two electrodes of the address electrode 5 and the scan electrode 2 intersecting with each other with the discharge space therebetween, the address pulse 15 is discharged. A method of applying the space charge control pulse 23 when it is applied within the sustain period 13 is shown in FIG. In this case, a space charge control pulse 23 having the same polarity as the discharge sustain pulse 16 is placed in the address electrode 5 immediately after the end of sustain discharge to control the space charge. 45 shows the case where the space charge control pulse 23 is applied immediately after the end of the sustain discharge and the space charge control pulse 23 is terminated after the discharge sustain pulse 16 is finished. FIG. 46 shows the discharge sustain pulse. In this case, the space charge control pulse 23 is applied and the space charge control pulse 23 is terminated before the discharge sustain pulse 16 ends. FIG. 47 shows the space charge at the same time as the discharge sustain pulse is applied. This is a case where the control pulse 23 is applied and the discharge sustain pulse 16 ends and the space charge control pulse 23 ends. FIG. 48 shows the space charge control pulse 23 before the discharge sustain pulse 16 is applied. Is a case where the space charge control pulse 23 is terminated before the discharge sustain pulse 16 is terminated. FIG. 49 shows the space charge control pulse 23 before the discharge sustain pulse is applied. (16) has ended This is the case where the space charge control pulse 23 is terminated later. The method of applying the discharge sustain pulse 16 and the space charge control pulse 23 is also applied to the positive discharge sustain pulse 16 as shown in FIGS. 50 to 55. That is, FIG. 50 shows the space charge control pulse 23 after the positive discharge sustain pulse 16 is applied and the positive space charge control pulse 23 is applied immediately after the end of the sustain discharge and before the discharge sustain pulse 16 ends. 51 is a case where the space charge control pulse 23 is applied immediately after the sustain discharge is finished and the space charge control pulse 23 is terminated after the discharge sustain pulse 16 is finished. 52 is a case where the discharge charge pulse is applied and the space charge control pulse 23 is applied and the space charge control pulse 23 is terminated before the discharge sustain pulse 16 ends. FIG. 53 shows the discharge sustain pulse. When the space charge control pulse 23 is applied and the discharge sustain pulse 16 is terminated and the space charge control pulse 23 is terminated at the same time, before the discharge sustain pulse 16 is applied. Apply the space charge control pulse 23 This is a case where the space charge control pulse 23 is terminated before the high discharge sustain pulse 16 ends, and FIG. 55 applies the space charge control pulse 23 before the discharge sustain pulse is applied and discharge discharge pulse 16. This is the case where the space charge control pulse 23 is terminated after the process is completed.

In the driving method of the two-electrode counter discharge structure, there is a method of applying the polarity of the space charge control pulse 23 opposite to the polarity of the discharge sustain pulse 16, as shown in Figs. In this driving method, it should be noted that the pulse 23 for space charge control is applied after the discharge by the discharge sustain pulse 16 is completed, and the electric field is sufficient to offset the electric field due to the wall charge generated by the discharge. It is preferable to limit the voltage of the space charge control pulse 23 to the voltage generated. That is, when the discharge holding pulse 16 is first applied to discharge and wall charge is formed, the space charge control pulse 23 is applied. However, the potential difference between the discharge holding pulse 16 and the space charge control pulse 23 at this time is applied. The voltage is not greater than the voltage enough to cancel the electric field due to wall charge than the discharge sustain pulse 16 voltage.

In the above-described embodiments, the temporal position of applying the space charge control pulse 23 to the discharge sustain pulse 16 can be applied in advance of the sustain discharge by the discharge sustain pulse 16 to overlap the discharge sustain pulse 16. It is also possible to apply immediately after the sustain discharge by the discharge sustain pulse 16 to overlap the discharge sustain pulse. The characteristics of this case are basically the same as described above. The end point of the space charge control pulse 23 may also be terminated earlier than the discharge sustaining pulse 16 on the basis of the discharge sustaining pulse 16, and may be terminated simultaneously with the discharge sustaining pulse 16, or the discharge sustaining pulse 16. It can also be terminated later than (16). The effect obtained in each case is as described above. In addition, the space charge control pulse 23 can perform the effective priming function by controlling the density distribution of the space charge immediately after the discharge not only in the AC discharge device but also in the DC discharge device.

The present invention can efficiently control the space charge to increase the wall charge conversion rate of the space charge, thereby lowering the discharge holding voltage and ensuring stable operation margin. Therefore, there is an effect of improving the rise of the discharge voltage and the decrease in the operating margin caused in the case of high speed driving, narrow pulse driving and the like.

Fig. 58 is a waveform diagram written for an experiment for analyzing the characteristics of the pulse for space charge control of the present invention. On the basis of the light output 24, a space charge control pulse 23 is applied to the address electrode 5 while delaying T _D at an interval of 200 ms from immediately after the end of the sustain discharge is completed. At the same time, the minimum discharge holding voltage (V _S ) at that time was measured by _{increasing the} space charge control pulse voltage (V _SCCP ) from 0V to 20V. Here, the minimum discharge holding voltage (V _S ) is a visual observation that the discharge block composed of a plurality of cells simultaneously and uniformly emits light, and the discharge holding pulse when the light output 24 of the photodetector always has a constant size and waveform. The minimum voltage of the voltage.

Fig. 59 shows the results of this experiment as a graph. It can be seen that as the space charge control pulse gets closer to the display discharge, the higher the space charge control pulse voltage is, the lower the display discharge holding voltage is.

FIG. 60 shows the relationship between the delay time T _D and the discharge sustain pulse voltage V _S of the space charge control pulse when the voltage of the space charge control pulse is constantly applied at 140V. The display discharge sustain pulse width (W _S ) was measured at 2 ㎲, 3 ㎲, and 4 는데. As a result, all three cases had similar display discharge sustain voltage (V _S ) within 1.2 지연 of delay time. . Therefore, the space charge is efficiently controlled in this section, and it is considered that a certain wall charge amount can be secured regardless of the display discharge sustain pulse width W _S. In other words, it can be said to have a constant discharge holding voltage (V _S ) irrespective of the display discharge holding pulse width (W _S ).

Figure 61 shows the relationship between space charge control of the pulse voltage (V _SCCP) and the discharge sustaining voltage (V _S) at the time sikyeoteul is a space-charge control pulse 23 immediately following the end of the display discharge. The discharge holding voltage V _S has a high value when the pulse voltage V _SCCP for space charge control is small. However, it can be seen that as the space charge control pulse voltage V _SCCP increases, the discharge sustain voltage V _S gradually decreases. When the discharge sustain pulse width V _S is changed with respect to each discharge sustain pulse width W _S , when the space charge control pulse voltage V _SCCP is low, the discharge sustain pulse width W _S is 2 ㎲. In the case of 3 and 4 와, the minimum discharge sustain pulse voltage (V _S ) is different, but when the space charge control pulse voltage (V _SCCP ) is gradually increased, the minimum discharge sustain pulse voltage is independent of the discharge sustain pulse width (W _S ). (V _S ) represents a constant value. Here, it can be seen that when the space charge control pulse voltage V _SCCP rises, a constant discharge sustain pulse voltage V _S can be obtained regardless of the discharge sustain pulse width W _S. However, when the display discharge sustain pulse width W _S is 3,4 ㎲, it can be seen that the discharge sustain pulse voltage V _S rises when the space charge control pulse voltage V _SCCP exceeds 140V. From this, it can be seen that the pulse voltage V _SCCP for the space charge control has an optimum point, so that a rise above a certain level causes the discharge sustain pulse voltage V _S to rise again. This is because the space charge control pulse 23 acts to hinder the accumulation of wall charges. Therefore, it can be seen that the space charge control action of the space charge control pulse 23 is related to the discharge sustain pulse voltage V _S and an optimization point exists. Referring to FIG. 61, when the discharge sustaining pulse width W _S is 3 and 4 변화, the change in the discharge sustaining pulse voltage V _S is consistent with the overall discharge. From this, the role of the space charge on the wall charge accumulation is It can be inferred that there is no meaning after about 3㎲. Therefore, it can be said that the width of the space charge control pulse 23 is preferably about 3 m 3 or less.

62 shows the minimum discharge sustain pulse voltage (V _S ) with respect to the change in the discharge sustain pulse width W _S when the space charge control pulse 23 is applied immediately after the discharge by the discharge sustain pulse 23 and the voltage is optimized. ) Is shown. As the discharge sustain pulse width W _S becomes narrower, the discharge sustain pulse voltage V _S increases, especially after 2 kV. This is due to the difference in mobility and attenuation characteristics of electrons and ions during space charge. That is, the ions of the space charges can survive up to 2 μs, but the electrons disappear before 2 μs. Thus, in the discharge sustain pulse 16 having a pulse width smaller than 2 μs, ions do not accumulate. (V _S ) can be said to rise rapidly. When the space charge control pulse 23 is applied, the discharge sustain pulse voltage V _S decreases significantly, especially about 1 V, about 29 V. Data for these experimental results are shown in Table 1. FIG. 63A and FIG. 63B are graphs of photographs of actual waveforms, in which the discharge sustain pulse voltage V _S is measured when the discharge sustain pulse width W _S is 1 kHz. The discharge sustain pulse voltage (V _S ) at the time of non-application and application was measured. From this, it can be seen that the pulse 23 for space charge control itself does not cause discharge. Of course, in the case of AC discharge, the generation of the displacement current by the space charge control pulse 23 can be expected, but it does not affect the discharge current. Therefore, it can be said that the current flowing in the discharge space is only caused by the flow of space charge generated by the sustain discharge.

Based on the above experimental results, the space charge control pulse according to the present invention can efficiently control the space charges generated by the display discharge, thereby increasing the conversion rate of the space charges to the wall charges, and as a result, it is possible to lower the discharge sustain pulse voltage. Do. In addition, since the remaining space charge can be reduced due to the efficient control of the space charge, it is possible to improve the stability of subsequent sustain discharges.

Claims (28)

A pair of side by side first and second electrodes which alternately apply discharge sustain pulses of the same polarity to cause sustain discharge; And a third electrode crossing the side-by-side pair of electrodes and applying a discharge address pulse to generate an address discharge with at least one of the pair of electrodes so that the discharge electrodes correspond to the discharge spaces corresponding to each pixel one-to-one. In the driving method of a discharge device which is formed in a matrix and causes discharge, Applying a space charge control pulse to the third electrode so as to overlap the application period of the discharge sustain pulse; A method of driving a gas discharge device comprising a. The method of claim 1, And the application of the space charge control pulse is started prior to the application period of the discharge sustain pulse, and the application of the space charge control pulse ends after the application period of the discharge sustain pulse ends. The method of claim 1, And the application of the space charge control pulse is started prior to the application period of the discharge sustain pulse, and the application of the space charge control pulse ends within the application period of the discharge sustain pulse. The method of claim 1, And the application of the space charge control pulse starts in the application period of the discharge sustain pulse, and the application of the space charge control pulse ends in the application period of the discharge sustain pulse. The method of claim 4, wherein When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. Immediately after the egg, the width of the space charge control pulse is 3 ~ sec within the driving method of the discharge device. The method of claim 4, wherein The time point at which the space charge control pulse is applied is after a predetermined time has passed since the discharge by the discharge sustain pulse ends, and the width of the space charge control pulse is within 3 ° sec. Way. The method of claim 1, And the application of the space charge control pulse starts within the application period of the discharge sustain pulse, and then the application of the space charge control pulse ends after application of the discharge sustain pulse. The method of claim 7, wherein When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. And a time point at which the space charge control pulse ends is a short time after the discharge sustain pulse ends. The method of claim 7, wherein When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. Immediately after the egg, the width of the space charge control pulse is 3 ~ sec within the driving method of the discharge device. The method of claim 7, wherein The time point at which the space charge control pulse is applied is after a predetermined time has passed since the discharge by the discharge sustain pulse ends, and the width of the space charge control pulse is within 3 ° sec. Way. The method of claim 1, The discharge sustain pulse is formed by attaching two pulses having different voltage values, followed by a small pulse of a relatively small voltage followed by a large pulse of a relatively large voltage, and the space charge control pulse coincides with a start point of the small pulse. And a gas discharge device is driven. The method of claim 1, Immediately after the discharge by the discharge sustain pulse, the space charge control pulse is started to be applied, and when the absolute value of the voltage of the discharge sustain pulse is 0V to 200V, the absolute value of the voltage of the space charge control pulse is 0V to 150V. The drive method of the discharge device characterized by the above-mentioned. The method of claim 1, And the discharge sustain pulse is applied to only one electrode of the pair of parallel electrodes. The method of claim 13, Wherein the discharge sustain pulses alternate pulses of opposite polarities, and the space charge control pulses have the same polarity in one-to-one correspondence with the discharge sustain pulses. The method of claim 14, The discharge sustain pulses of opposite polarities are formed by attaching two pulses having different voltage values, respectively, by adding a small pulse of a relatively small voltage followed by a large pulse of a relatively large voltage, and the space charge control pulse is the small pulse. And applying at the start of the gas discharge apparatus. The method of claim 1, And the discharge sustain pulses are pulses of the same polarity alternately applied to the pair of parallel electrodes in time, and the space charge control pulse has the same polarity as the discharge sustain pulse. The method of claim 1, And the application of the space charge control pulse is started prior to the application period of the discharge sustain pulse, and the application of the space charge control pulse ends after the application period of the discharge sustain pulse ends. The method of claim 16, And the application of the space charge control pulse is started prior to the application period of the discharge sustain pulse, and the application of the space charge control pulse ends within the application period of the discharge sustain pulse. The method of claim 16, And the application of the space charge control pulse starts in the application period of the discharge sustain pulse, and the application of the space charge control pulse ends in the application period of the discharge sustain pulse. The method of claim 19, When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. Immediately after the egg, the width of the space charge control pulse is 3 ~ sec within the driving method of the discharge device. The method of claim 19, The time point at which the space charge control pulse is applied is after a predetermined time has passed since the discharge by the discharge sustain pulse ends, and the width of the space charge control pulse is within 3 ° sec. Way. The method of claim 16, And the application of the space charge control pulse starts within the application period of the discharge sustain pulse, and then the application of the space charge control pulse ends after application of the discharge sustain pulse. The method of claim 22, When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. And a time point at which the space charge control pulse ends is a short time after the discharge sustain pulse ends. The method of claim 22, When the space charge control pulse is applied, the discharge by the discharge sustain pulse ends. Immediately after the egg, the width of the space charge control pulse is 3 ~ sec within the driving method of the discharge device. The method of claim 22, The time point at which the space charge control pulse is applied is after a predetermined time has passed since the discharge by the discharge sustain pulse ends, and the width of the space charge control pulse is within 3 ° sec. Way. The method of claim 16, The discharge sustain pulse is formed by attaching two pulses having different voltage values, followed by a small pulse of a relatively small voltage followed by a large pulse of a relatively large voltage, and the space charge control pulse coincides with a start point of the small pulse. And a gas discharge device is driven. The method of claim 26, The pair of parallel electrodes corresponding to the space charge control pulses have a voltage level smaller than that of the small pulses between the discharge sustain pulses and has a polarity opposite to that of the space charge control pulses. And further applying pulses. The method of claim 16, The space charge control pulse starts to be applied immediately after the discharge by the discharge sustain pulse, and when the absolute value of the voltage of the discharge sustain pulse is 0V to 200V, the absolute value of the space charge control pulse voltage is 0V to 150V. A method of driving a discharge device, characterized in that.

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