KR940004437B1 - Dc type plasma display panel and driving method therfof - Google Patents

Abstract

The DC plasma display panel and driving method comprises front and rear substrates having a discharge space into which gas is filled, a first electrode formed on one substrate, a second electrode perpendicular to and spaced apart from the first electrode, and multiple barriers for preventing crosstalk between cells formed on the intersections of the first and second electrodes, wherein a diffusing means is provided to form a disturbance electric field in the discharge area between the first and second electrodes with periodic or nonperiodic pulse voltage of frequency and disturb and distort the path of charged particles produced by the discharge between the first and second electrodes, thereby facilitating the control of grey scale.

Description

DC plasma display panel and driving method

Figure 1 shows the structural concept of the cell of the PDP of the present invention.

2 and 3 are schematic cross-sectional views showing an embodiment of the PDP of the present invention.

4 is a schematic view showing the electrode arrangement of the PDP according to the present invention.

5 to 14 are diagrams illustrating the characteristics of the PDP according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct current plasma display panel and a method of driving the same. Particularly, a direct current plasma display panel (PDP; Plasma display) of a double pulse memory (DPM) type with improved response when the discharge efficiency is high panel) and its driving method.

In recent years, the development of high-definition television has been partially completed, and the improvement plan has been continuously studied, and the importance of an image display medium, that is, an image display device, has become more important. The research subjects are color cathode ray tubes, liquid crystal display panels, electroluminescent flat panel display devices, fluorescent display tubes, and plasma display panels, which are expected to maintain their position as main display devices for a considerable period of time. However, since it is not technically completed as a display element that can be satisfied with the development of high-definition television, it is being developed while maintaining a complementary relationship at different positions.

In the display device and the like as described above, the plasma display panel (hereinafter, abbreviated as PDP) is gradually becoming the most promising display element in this field because it is suitable for displaying large-scale images, which is thin in spite of its large appearance. This is of course because of its high luminance resolution and illuminance ratio.

In general, PDPs are roughly classified into a direct current type and an alternating current type by a discharge method according to the structure thereof, and are further divided into memory types and non-memory types. DC-type memory PDP is a test PDP manufactured and researched by NHK research institute in Japan. It uses DC pulse voltage and adopts so-called Planar Pulse Memory (PPM) method. It is in the form of producing and supplying prime charged particles before cooking.

However, the PPM PDP of the PPM method is continuously under study because it does not meet the level required by high-definition television in terms of luminous brightness, discharge efficiency and illuminance ratio, and one of the biggest disadvantages of the PDP is that it consumes more power than other display devices. There is a lot. The reason for this is the supply of prime particles for high drive voltage and addressing time control. Moreover, the first problem to be solved in PDP is efficiency problem. In fact, PDP is still falling behind in competition with other display devices due to low efficiency. Such a conventional PDP has been studied in various fields in order to become a problem as described above, and is mainly focused on physical structure improvement and development of materials for electrodes. For example, in order to improve the luminance, in the case of a color PDP, the length of the electrodes is extended to the maximum to obtain a sufficient amount of ultraviolet rays. In order to improve the discharge efficiency, the structure of the cathode or the material thereof is changed. To increase the secondary electron emission efficiency. In particular, in the auxiliary discharge type PDP, improvements have been made in improving the electrode and the neighboring elements in order to efficiently generate the charged particles and to efficiently use the generated charged particles. On the other hand, the method for improving the illuminance ratio mainly corresponds to those in the form of the auxiliary discharge method to change the electrode arrangement structure and the like so that the auxiliary discharge light is not visible from the front.

As mentioned above, the results of the conventional research on the PDP are still inadequate to develop a satisfactory PDP.

The present invention provides a PDP having a new concept of discharge mode as a result of the above research activities.

SUMMARY OF THE INVENTION An object of the present invention is to provide a PDP and a driving method thereof capable of displaying an image having a high luminance with a low discharge sustain voltage and a higher discharge efficiency than a conventional PDP under an allowed discharge voltage.

In order to achieve the above object, the PDP of the present invention includes a front plate and a rear plate for providing a discharge space in which the discharge gas is filled; A strap-shaped first electrode formed on any one of the front plate and the back plate; A stripe-shaped second electrode formed on one of the front plate and the back plate to be orthogonal to the first electrode and to maintain a predetermined gap therebetween; A plasma display panel having a plurality of parallel partition walls for preventing cross-talk between a plurality of cells formed at each intersection of the first electrode and the second electrode, wherein the first electrode and the second electrode are defined in a discharge region between the first electrode and the second electrode. A characteristic feature is that diffusion means is provided which forms a disturbing electric charge with a pulse voltage of periodic or aperiodic frequency and disturbs and distorts the propagation path of the charged particles generated by the discharge between the first electrode and the second electrode.

In addition, the driving method of the PDP of the present invention, which achieves the above object, forms a discharge cell in a predetermined pattern of a cathode and an anode between a front plate and a back plate to which discharge gas is filled, and an auxiliary electrode in the vicinity of the discharge cell. A method of driving a PDP of a type provided, wherein a first DC pulse having a predetermined voltage and a period is applied to the cathode and the anode constituting the discharge cell, and a frequency of the first DC pulse is applied to the auxiliary electrode. Rather than having a higher frequency, a voltage having a lower potential than the first DC pulse is applied.

In the above-mentioned PDP of the present invention, the diffusion means is formed in parallel with the second electrode or the first electrode at a predetermined distance, and the auxiliary electrode is formed by the auxiliary electrode on a stripe to which a high frequency direct current pulse is applied. May be functionally referred to as a diffusion electrode or a disturbing electrode.

The second electrode and the first electrode maintain the mutual discharge potential, and a direct current pulse of a predetermined period is applied to the auxiliary electrode, so that gas ions and charged particles moving between the electrodes are transferred to the auxiliary electrode. It will be disturbed and diffused by the local advance formed by it.

At this time, a DC pulse having a predetermined period for discharging (display discharge) is applied to the first electrode and the second electrode, and a DC pulse having a faster cycle than the DC pulse for the discharging is applied to the auxiliary electrode. At this time, the voltage applied is maintained at a potential that does not cause a discharge with the second electrode and the first electrode, the potential can be maintained to the extent that some prime particles are generated, if necessary.

The PDP of the present invention does not linearly move ions and electrons between the electrodes by the diffusion means, but diffuses in a wave form by a locally disturbed electric field, so that the particles can be trapped in the discharge space for a long time. Will appear.

Due to the diffusion effect, a large amount of secondary electrons can be generated, and the minimum discharge holding voltage required for maintaining the discharge during kitchen cooking is reduced, and the discharge, so-called afterglow ( After grow). That is, the diffused prime particles remain until the after-glow period to assist the electric discharge, thereby improving the discharge delay at the start of the display discharge, thereby improving responsiveness. Therefore, when operating under the same conditions as a conventional PDP, it is possible to reduce the power consumption by having a low discharge voltage is faster response and higher luminance than a conventional PDP.

Hereinafter, preferred embodiments of the present invention will be described in detail.

1 is a conceptual diagram of a unit discharge cell showing a unit cell shell in the PDP of the present invention, and FIG. 2 is a schematic cross-sectional view of a PDP based on the concept of the present invention. First, the basic concept of operation of the PDP of the present invention will be described with reference to FIG.

A positive electrode 1 (also referred to as a main electrode in the future) and a negative electrode 2 in one discharge cell filled with a discharge gas are located opposite each other, and in the vicinity of the discharge region therebetween, a characteristic element of the present invention. An auxiliary electrode 3 as a so-called disturbance and diffusion electrode is provided. A relatively low frequency direct current pulse is applied to the anode 1 and the cathode 2, and a relatively high frequency positive potential DC pulse is applied to the auxiliary electrode 3. At this time, the voltage applied to the auxiliary electrode (3) is a potential that does not cause a discharge of the relative potential difference between the anode (1) and the cathode (2) or a degree that can bring about a slight prime effect if necessary Has a potential. In the above structure, the auxiliary electrode 3 is one of essential components of the diffusion means, which is a feature of the present invention, and in addition to the physical structure itself adjacent to the discharge region between the anode 1 and the cathode 2, the anode The type of driving voltage applied to the auxiliary electrode 3 in order to disturb the electric field between (1) and the cathode (2) is also one of the essential configurations of the present invention. Therefore, the diffusion means in the present invention has an essential configuration of the auxiliary electrode in a state where a pulse voltage having a predetermined potential and frequency is applied. Of course, a driving device for applying a voltage having an appropriate frequency to the auxiliary electrode is required for the diffusion means, which can be easily achieved by changing the existing PDP drive circuit, and thus description thereof will be omitted.

In the discharge cell having the above structure and voltage application method, the discharge starts when the space insulation is destroyed by the electric field induced between the anode 1 and the cathode 2, and the auxiliary electrode 3 has a zero potential. In the case of (ground potential), it is made through the shortest path in a straight line in the moving direction of the charged particles. However, at this time, when a high potential DC pulse of medium potential is applied to the auxiliary electrode 3, a gap between the anode 1 and the cathode 2 is caused by a periodic or aperiodic disturbance electric field formed around the auxiliary electrode. The electric field is distorted at a predetermined cycle. As a result, the equipotential lines between the anode 1 and the cathode 2 are distorted by the electric field by the auxiliary electrode, and the charged particles passing through the waveguides have a wavy shape due to the distorted coincidence lines as shown in FIG. 6) the diffusion will proceed.

Such a discharge system results in extending the traveling distance of the charged particles in the limited cell 5, that is, in the limited discharge space. The longer the moving distance of the charged particles, the longer the trapping time of the charged particles in the discharge space, which promotes the generation of more secondary electrons, which increases the brightness as well as the subsequent after-sales. By remaining charged particles diffused to the glow time, the afterglow can be easily formed.

Hereinafter, the present invention will be described in more detail with reference to the following examples.

As shown in FIG. 2, the PDP of the present invention is provided with a front plate 10 and a back plate 20 with a plurality of side-by-side partition walls 30 interposed therebetween, as in a conventional PDP. ), A stripe-shaped anode 40 serving as the first electrode in the same direction as the partition wall 30 is alternately formed with the partition wall 30. An auxiliary electrode 50 serving as a disturbing and diffusing means is provided between the anode 40 and the partition wall 30 adjacent to one side thereof so that the anode 40 and the auxiliary electrode 50 are disposed between the partition walls 30. It shows a structure arranged in pairs. On the other hand, the back plate 20 is provided with a plurality of cathodes (60) as a stripe-shaped second electrode which is located orthogonal to the anode (40). The PDP having such a structure has an electrode arrangement relationship as shown in FIG. 4, and was manufactured regularly as shown in the following table for practical application.

TABLE 1

Here, the cathode and the anode used a nickel face known as DuPont 9535 for the convenience of fabrication of specimens, and the terminal for each electrode used a silver paste known as DuPont 77131.

Specific configuration examples of the positive electrode or the negative electrode mentioned above are intended to show one embodiment, and it will be apparent that modifications can be made in various forms based on the basic concept of the present invention. For example, as shown in FIG. 3, the position of the auxiliary electrode 50 is changed from the front plate 10 to the back plate 20, but is orthogonal to the upper portion of the sieve cathode through the insulating layer 70. In addition, all electrodes may be located on the rear plate by using a so-called planar discharge method. On the other hand, the positive electrode DC voltage is applied to the auxiliary electrode, but the voltage of the negative potential may be applied, the disturbance and diffusion of the charged particles to the electric field by the auxiliary electrode should be made.

The characteristics of the PDP of the present invention manufactured as described above were measured by inspection equipment, and the following results were obtained. The following description will be made with reference to FIGS. 3 to 14.

5 shows the change of the discharge start voltage and the minimum discharge sustain voltage according to the change of the discharge pulse, that is, the glow discharge possible region. In this case, as the voltage is not applied to the auxiliary electrode for the experiment, it is shown that the discharge voltage increases as the frequency increases.

The discharge region, that is, the voltage band between the discharge start voltage and the sustain voltage, becomes a stable operation region of a pulse for a memory function. The larger the region is, the more stable operation is guaranteed, but the maximum discharge voltage, that is, the discharge start voltage, Nothing can be done and the discharge minimum voltage is subject to the discharge environment. Therefore, it is more practical to lower the discharge sustain voltage to increase the operating area.

FIG. 6 shows an operating area when a DC pulse of 1 KHz is applied and a simple DC voltage is applied to the auxiliary electrode for discharging. This case corresponds to the driving method of PPM of NHK R & D in Japan. Prime particles are generated and supplied by auxiliary discharge, but the minimum holding voltage is virtually unchanged as shown in the diagram of this figure. However, FIG. 7 shows the results of the DPM method of the present invention, that is, a method of applying independent DC pulses to the anode and the auxiliary electrode, respectively. The minimum voltage of the discharge sustain voltage according to the pulse frequency and the peak voltage of the auxiliary electrode is changed. Show the change.

As can be seen from this, when the frequency applied to the auxiliary electrode is lower than or equal to the frequency applied to the auxiliary electrode (1KHz) for discharging, the minimum holding voltage is almost unchanged, gradually increasing the frequency of the pulse to the auxiliary electrode minimum discharge maintenance The voltage will gradually decrease. At this time, when the voltage of the highest value of the pulse applied to the auxiliary electrode is increased, the minimum discharge sustain voltage is further lowered due to the synergistic effect. In conclusion, applying a DC pulse of higher frequency than the anode to the auxiliary electrode can lower the minimum discharge sustain voltage, and vice versa.

In addition, FIG. 8 shows the increase and decrease of the memory coefficient according to the frequency change. As a result, the memory coefficient increases as the frequency increases.

On the other hand, the influence of the DC pulse of the auxiliary electrode on the delay time for determining the addressing time when driving the PDP was investigated. FIG. 9 shows the change of the delay time according to the voltage change when a pulse of 1 mesc and 0.12 msce is applied to the auxiliary electrode, and the delay time is significantly reduced as the voltage of the auxiliary electrode is increased. Can be.

FIG. 10 shows the change of the delay time according to the DC pulse frequency when the DC pulse voltage of the auxiliary electrode is fixed at 150V. As the frequency of the DC pulse of the auxiliary electrode increases, that is, the greater the frequency of the DC pulse between the main electrode (anode) and the cathode, the greater the delay time.

As described above, the PDP of the present invention takes a discharge method having a different concept from that of the conventional PDP. Conventionally, the role of reducing the delay time in the operation of the PDP has been played by the prime particles generated from the neighboring electrodes, but the auxiliary electrode of the PDP of the present invention functions as an external charged particle by controlling the glow of the discharge. In addition to improving the delay time by controlling their own charged particles (self-prime).

11 and 12 show an experimental result of measuring relative luminance of one pixel. First, FIG. 11 shows a main electrode (positive electrode) according to a change of a DC pulse voltage when a period of a DC pulse of an auxiliary electrode is 0.1 msec. The light emission luminance is obtained by the DC pulse of 1 msec. As can be seen from this, the brightness increases as the DC pulse voltage increases. 12 is a result of changing the DC pulse voltage of the auxiliary electrode to 150V and changing the frequency of the DC pulse of the auxiliary electrode, indicating that the luminance increases with increasing frequency. The experimental results show that the change of frequency and voltage of the DC pulse can be controlled by appropriately controlling the diffusion and afterglow of the charged particles. That is, the diffusion of particles or the control of the after glow can improve the luminance of the pixel, and the improvement of the gray scale can be performed without changing the pulse duty ratio or the amount of current flowing in the pixel. ) Can be improved. In addition, the luminance can be improved and the delay time can be adjusted regardless of the prime particles, thereby improving the luminous efficacy.

13 and 14 are experimental results of the efficiency measured by the DPM cell of the present invention. FIG. 13 shows the improvement of the efficiency of one cell according to the pulse voltage change of the auxiliary electrode. 14 shows an improvement in efficiency according to the change of the auxiliary pulse frequency. In other words, the diffusion of the auxiliary electrode and the control of the after glow have improved in terms of efficiency. Of course, a little power consumption is increased by applying a pulse to the auxiliary electrode, but the overall efficiency is improved in consideration of the brightness improvement. In this case, since prime particles are not supplied and are driven while improving the delay time as shown in the above delay improvement experiment, more efficiency improvement is expected than the PPM method.

As described above, the PDP of the present invention is significantly superior to the conventional PDP in terms of memory capacity, delay time, brightness, and efficiency, and the basic principle thereof is diffusion of charged particles and afterglow as described above. By adjusting the plasma properties. This invention is, of course, not limited to any particular structure as described above. In other words, any PDP having a diffusing means for forming a diffused electric field in the vicinity of the discharging region is within the scope of the present invention.

To summarize the effects of the present invention, the operating area for the memory function increases with the increase in the pulse voltage and frequency of the auxiliary electrode, and faster addressing is possible due to the reduction of the delay time. Increasing the frequency leads to an improvement in luminance, so that gray scale control is easy and the efficiency is superior to other PDPs.

Claims (9)

A front plate and a back plate for providing a discharge space in which the discharge gas is filled; A first electrode on a strip formed on one of the front and back plates; A stripe-shaped second electrode formed on one of the front plate and the back plate so as to be perpendicular to the first electrode and to maintain a predetermined distance therebetween; A plasma display panel having a plurality of parallel partition walls for preventing cross-talk between a plurality of cells formed at each intersection of the first electrode and the second electrode, wherein the discharge region between the first electrode and the second electrode; And a diffusion means for forming a disturbing electric field at a pulse voltage of a predetermined periodic or aperiodic frequency to disturb and distort the propagation path of the charged particles generated by the discharge between the first electrode and the second electrode. panel. The method of claim 1, wherein the diffusion means is disposed in parallel to at least one of the first electrode and the second electrode, the diffusion means of a frequency higher than the DC pulse voltage applied to the first electrode and the second electrode And an auxiliary electrode to which a pulse voltage is applied. The plasma display panel of claim 1, wherein the auxiliary electrode is formed on one of a front plate and a back plate in parallel with the first electrode. The plasma display panel of claim 3, wherein the first electrode and the auxiliary electrode are formed side by side on the front plate. The plasma display device of claim 3, wherein the second electrode is formed on the rear plate, and the auxiliary electrode is formed orthogonal to the second electrode with an insulating layer interposed therebetween. Display panel. The plasma display panel of claim 5, wherein the first electrode is formed on an inner surface of the front plate in a direction orthogonal to the second electrode. A method of driving a plasma display panel in which a cathode and an anode form a predetermined discharge cell in a predetermined pattern between a front plate and a back plate to which discharge gas is filled, and an auxiliary electrode is disposed in the vicinity of the discharge cell. And distorting and distorting the discharging region between the cathodes to a voltage of a predetermined potential applied to the auxiliary electrode. The method of claim 7, wherein a first DC pulse voltage having a predetermined voltage and a period is applied to the cathode and the anode constituting the discharge cell, and the auxiliary electrode has a frequency higher than that of the first DC pulse. And a second DC pulse voltage having a potential lower than the first DC pulse voltage. The method of driving a plasma display panel according to claim 8, wherein the voltage applied to the auxiliary electrode has a potential equal to or lower than a discharge start voltage together with the counter electrode.