KR100315125B1 - Plasma Display Panel - Google Patents

Abstract

The present invention relates to a plasma display panel capable of obtaining a high luminous efficiency.

The plasma display panel of the present invention includes a scan / sustain electrode and a common sustain electrode formed on the upper substrate so as to be disposed at an edge of the discharge cell, and a first substrate formed on the upper substrate so as to be disposed between the scan / sustain electrode and the common sustain electrode. And formed on the upper substrate to cover the second trigger electrode, the scan / sustain electrode, the common sustain electrode, the first and second trigger electrodes, and the first and second trigger electrode sides than the scan / sustain electrode and the common sustain electrode side. The dielectric layer is set to have a thin thickness.

According to the present invention, the trigger electrode is formed at the center of the upper substrate, and the scan / sustain electrode and the common sustain electrode are formed at the edge of the upper substrate to generate discharge at the edge of the light emitting cell, thereby improving the luminous efficiency as well as the trigger electrode. The thickness of the center portion and the edge of the upper dielectric layer in which they are formed is set differently or the dielectric constant is different to lower the voltage drop caused by the dielectric layer. As a result, power consumption can be reduced, and trigger discharge can be stabilized.

Description

Plasma Display Panel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly to a plasma display panel capable of obtaining high luminous efficiency.

Plasma Display Panel (hereinafter referred to as 'PDP') is a display device using visible light generated from a phosphor when vacuum ultraviolet rays generated by gas discharge excite the phosphor. PDP is thinner and lighter than Cathode Ray Tube (CRT), which has been the mainstay of display means, and has the advantage of being able to realize high definition large screen. PDP is composed of a plurality of discharge cells arranged in a matrix form, one discharge cell constitutes a pixel of the screen.

1 is a perspective view showing a discharge cell structure of a conventional AC surface discharge PDP.

Referring to FIG. 1, a discharge cell of a conventional AC surface discharge type PDP is formed on a scan / sustain electrode 12Y and a common sustain electrode 12Z formed on an upper substrate 10, and a lower substrate 18. The address electrode 20X is provided. The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan / sustain electrode 12Y and the common sustain electrode 12Z side by side. In the upper dielectric layer 14, wall charges generated during plasma discharge are accumulated. The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge and increases emission efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used. The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the address electrode 20X is formed, and the phosphor layer 26 is coated on the surfaces of the lower dielectric layer 22 and the partition wall 24. The address electrode 20X is formed in the direction crossing the scan / sustain electrode 12Y and the common sustain electrode 12Z. The partition wall 24 is formed in parallel with the address electrode 20X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells. The phosphor layer 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided between the upper substrate 10 / lower substrate 18 and the partition wall 24.

The AC surface discharge type PDP is driven by dividing one frame into several subfields having different discharge times in order to express gray level of an image. Each subfield is further divided into a reset period for uniformly generating discharge, an address period for selecting a discharge cell, and a sustain period for expressing gray scale according to the number of discharges. For example, when the image is to be displayed with 256 gray levels, the frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields. Each of the eight subfields is further divided into an address period and a sustain period. Here, the reset period and the address period of each subfield are the same for each subfield, while the sustain period is 2 ⁿ (n = 0,1,2,3,4,5,6,7) in each subfield. Is increased. In this way, since the sustain period is changed in each subfield, the gray level of the image can be expressed.

Here, in the reset period, a reset pulse is supplied to the scan / sustain electrode 12Y to cause a reset discharge. In the address period, scan pulses are supplied to the scan / sustain electrodes 12Y, and data pulses are supplied to the address electrodes 20X to generate address discharges between the two electrodes 12Y and 20X. During the address discharge, wall charges are formed in the upper and lower dielectric layers 14 and 22. In the sustain period, sustain discharge is generated between the two electrodes 12Y and 12Z by an alternating current signal alternately supplied to the scan / sustain electrode 12Y and the common sustain electrode 12Z.

However, in the conventional AC surface discharge PDP, the sustain discharge space is concentrated in the center of the upper substrate 10, thereby decreasing the utilization of the discharge space. Accordingly, there is a problem that the discharge area is reduced and the luminous efficiency is reduced.

Accordingly, an object of the present invention is to provide a plasma display panel capable of improving luminous efficiency.

1 is a perspective view showing a discharge cell structure of a conventional AC surface discharge PDP.

2 is a perspective view showing a discharge cell structure of an AC surface discharge PDP according to a first embodiment of the present invention;

3 is a side view of the AC surface discharge PDP shown in FIG. 2;

4 is a diagram showing an AC surface discharge PDP according to a second embodiment of the present invention.

5 is a diagram showing an AC surface discharge PDP according to a third embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

10,30: upper substrate 12Y, 32Y: scan / sustain electrode

12Z, 32Z: common sustain electrode 14,36,22,44,50,52,54,56: dielectric layer

16,38: protective film 18,40: lower substrate

20X, 42X: address electrode 24, 46: partition wall

26,48: phosphor 34Y, 34Z: trigger electrode

In order to achieve the above object, the plasma display panel according to the present invention has a scan / sustain electrode and a common sustain electrode formed on an upper substrate so as to be disposed at an edge of a discharge cell, and an upper portion of the plasma display panel to be disposed between a scan / sustain electrode and a common sustain electrode. The first and second trigger electrodes formed on the substrate, and the scan / sustain electrode, the common sustain electrode, and the first and second trigger electrodes formed on the upper substrate so as to cover the first and second trigger electrodes and the first and second trigger electrodes. And a dielectric layer having a thin thickness on the second trigger electrode side.

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

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 2 to 5.

2 is a perspective view showing the discharge cell structure of the AC surface discharge PDP according to the first embodiment of the present invention.

Referring to FIG. 2, the AC surface discharge type PDP according to the first embodiment of the present invention includes first and second trigger electrodes 34Y and 34Z formed on the upper substrate 30 so as to be positioned at the center of the discharge cell, and edges of the discharge cell. The scan / sustain electrode 32Y and the common sustain electrode 32Z, the trigger electrodes 34Y and 34Z, the scan / sustain electrode 32Y and the common sustain electrode 32Z formed on the upper substrate 30 so as to be positioned at And an address electrode 42X formed in the center portion of the lower substrate 40 in a direction perpendicular to each other. The upper dielectric layer 36 and the protective film 38 are formed on the upper substrate 30 having the scan / sustain electrode 32Y, the first trigger electrode 34Y, the second trigger electrode 34Z, and the common sustain electrode 32Z side by side. This is laminated. The lower dielectric layer 44 and the barrier rib 46 are formed on the lower substrate 40 on which the address electrode 42X is formed, and the phosphor layer 48 is coated on the surfaces of the lower dielectric layer 44 and the barrier rib 46. The trigger electrodes 34Y and 34Z formed at a narrow interval Ni in the center of the discharge cell are used to start sustain discharge by receiving an AC pulse during the sustain period. The scan / sustain electrode 32Y and the common sustain electrode 32Z formed at a wide interval Wi at the edge of the discharge cell are supplied with alternating current pulses during the sustain period, and then discharge is started between the trigger electrodes 34Y and 34Z. Used to maintain.

3 to 5 show that the upper substrate is rotated 90 ° with respect to the lower substrate to show all the electrode structures in one discharge cell.

The operation process will be described in detail with reference to FIG. 3 as follows.

The AC surface discharge type PDP according to the first embodiment of the present invention is driven by dividing one frame into several subfields having different discharge times in order to express gray levels of an image. Each subfield is further divided into a reset period for uniformly generating discharge, an address period for selecting a discharge cell, and a sustain period for expressing gray scale according to the number of discharges. In the reset period, a reset pulse is supplied to the second trigger electrode 34Z of the discharge cell to generate reset discharge for initializing the discharge cell. In the address period, scan pulses are sequentially supplied to the first trigger electrode 34Y, and data pulses synchronized with the scan pulses are supplied to the address electrodes 42X. At this time, an address discharge occurs in the discharge cell supplied with data. In the sustain period, alternating pulses of different levels are alternately applied to the first and second trigger electrodes 34Y and 34Z, the scan / sustain electrodes 32Y, and the common sustain electrode 32Z. First, when a discharge is started between the first and second trigger electrodes 34Y and 34Z, two between the scan / sustain electrode 32Y and the common sustain electrode 32Z due to the priming effect of the charged particles generated at this time. Differential discharges are induced. Even if the distance Wi between the scan / sustain electrode 32Y and the common sustain electrode 32Z is large, the discharge can be performed even with sustain pulses having a relatively low voltage level due to the priming discharge between the first and second trigger electrodes 34Y and 34Z. It can be raised. By using this method, the discharge is primarily initiated using the trigger electrodes 34Y and 34Z formed at a narrow interval Ni, thereby suppressing the rise of the discharge start voltage, while the scan / sustain electrode 32Y and the common electrode are controlled by the priming effect. A long sustain discharge path may occur between the sustain electrodes 32Z. Thus, the amount of ultraviolet rays is increased, and the light emitting area is increased to improve the light emitting efficiency.

In the AC surface discharge PDP according to the first embodiment of the present invention, it is necessary to apply a voltage as low as possible between trigger electrodes so as to increase discharge efficiency without light emission, thereby minimizing unnecessary power consumption at the trigger electrode. . However, due to the thickness of the upper dielectric layer 36, a high voltage must be applied between the trigger electrodes 34Y and 34Z. Accordingly, there is a problem that the discharge efficiency is lowered by the voltage drop of the upper dielectric layer 36.

4 shows an AC surface discharge PDP according to a second embodiment of the present invention.

Referring to FIG. 4, the AC surface discharge PDP according to the second embodiment of the present invention includes an upper dielectric layer 50 having an edge and a step. The upper dielectric layer 50 is divided into a portion where the scan / sustain electrode 32Y and the common sustain electrode 32Z are formed, and a portion where the trigger electrodes 34Y and 34Z are formed. The upper dielectric layer 50 formed on the scan / sustain electrode 32Y and the common sustain electrode 32Z maintains the thickness as in the first embodiment of the present invention. However, the thickness Tthin of the upper dielectric layer 50 formed on the trigger electrodes 34Y and 34Z is set smaller than the reference thickness Tthick.

The detailed operation process according to the second embodiment of the present invention is as follows. First, in the reset period, a reset pulse is supplied to the second trigger electrode 34Z of the discharge cell to generate reset discharge for initializing the discharge cell. At this time, since the thickness Tthin of the upper dielectric layer 50 formed on the second trigger electrode 34Y is set smaller than the reference thickness Tthick, reset discharge may be performed at a low voltage. In the address period, scan pulses are sequentially supplied to the first trigger electrode 34Y, and data pulses synchronized with the scan pulses are supplied to the address electrodes 42X. At this time, an address discharge occurs in the discharge cell supplied with data. In the sustain period, alternating pulses of different levels are alternately applied to the first and second trigger electrodes 34Y and 34Z, the scan / sustain electrodes 32Y, and the common sustain electrode 32Z. First, primary discharge occurs between the first and second trigger electrodes 34Y and 34Z to generate charged particles. At this time, since the thickness of the upper dielectric layer 50 formed on the first and second trigger electrodes 34Y and 34Z is less than or equal to the reference thickness, the voltage drop by the upper dielectric layer 50 is reduced. That is, since the voltage drop of the upper dielectric layer 50 is small, the primary discharge can be performed between the first and second trigger electrodes 34Y and 34Z with the small voltage. When the discharge is started between the first and second trigger electrodes 34Y and 34Z, between the scan / sustain electrode 32Y and the common sustain electrode 32Z formed at the edge of the discharge cell due to the priming effect of the charged particles generated at this time. Secondary discharge is induced. Even if the interval between the scan / sustain electrode 32Y and the common sustain electrode 32Z is long, a long distance discharge can be caused by a sustain pulse of a relatively low voltage level due to the priming discharge between the first and second trigger electrodes 34Y and 34Z. . By applying a low voltage to the trigger electrodes 34Y and 34Z in this manner to perform primary discharge, the scan / sustain electrode 32Y and the common sustain electrode 32Z are prevented by the priming effect while suppressing an increase in the discharge start voltage. A long discharge path can cause sustain discharge in the liver. Thus, the luminous area is increased to improve luminous efficiency.

5 shows an AC surface discharge PDP according to a third embodiment of the present invention.

Referring to FIG. 5, the AC surface discharge PDP according to the third embodiment of the present invention includes upper dielectric layers 52, 54, and 56 having dielectric constants different from edges and centers thereof. The upper dielectric layers 52, 54, and 56 are divided into a portion where the scan / sustain electrode 32Y and the common sustain electrode 32Z are formed and a portion where the trigger electrodes 34Y and 34Z are formed. The upper dielectric layers 52 and 54 formed on the scan / sustain electrode 32Y and the common sustain electrode 32Z maintain the reference dielectric constant as in the first embodiment of the present invention. However, the dielectric constant of the upper dielectric layer 56 formed on the trigger electrodes 34Y and 34Z is set lower than the reference dielectric constant. Accordingly, even when the voltage levels of the scan pulses and the sustain pulses of the trigger electrodes 34Y and 34Z are lowered, address discharge and sustain discharge can be caused.

As described above, according to the plasma display panel according to the present invention, the trigger electrode is formed at the center of the upper substrate, and the scan / sustain electrode and the common sustain electrode are formed at the edge of the upper substrate to generate a discharge at the edge of the light emitting cell. The luminous efficiency is improved. In particular, according to the plasma display panel according to the present invention, the thickness of the center portion and the edge of the upper dielectric layer in which the trigger electrodes are formed are set differently or the dielectric constant is different to reduce the voltage drop caused by the dielectric layer. As a result, power consumption can be reduced, and trigger discharge can be stabilized.

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

Claims (5)

A scan / sustain electrode and a common sustain electrode formed on the upper substrate to be disposed at an edge of the discharge cell; First and second trigger electrodes formed on the upper substrate to be disposed between the scan / sustain electrode and the common sustain electrode; It is formed on the upper substrate to cover the scan / sustain electrode, the common sustain electrode, the first and the second trigger electrode, and the thickness of the first and second trigger electrode sides is greater than that of the scan / sustain electrode and the common sustain electrode side. And a dielectric layer set thinly. The method of claim 1, And an address electrode on the lower substrate to cause an address discharge with any one of the first and second trigger electrodes. A scan / sustain electrode and a common sustain electrode formed on the upper substrate to be disposed at an edge of the discharge cell; First and second trigger electrodes formed on the upper substrate to be disposed between the scan / sustain electrode and the common sustain electrode; It is formed on the upper substrate to cover the scan / sustain electrode, the common sustain electrode, the first and the second trigger electrode, and the dielectric constant of the first and second trigger electrode sides is greater than that of the scan / sustain electrode and the common sustain electrode side. And a dielectric layer set low. The method of claim 3, wherein And an address electrode on the lower substrate to cause an address discharge with any one of the first and second trigger electrodes. A scan / sustain electrode and a common sustain electrode formed on the upper substrate to be disposed at an edge of the discharge cell; First and second trigger electrodes formed on the upper substrate to be disposed between the scan / sustain electrode and the common sustain electrode; It is formed on the upper substrate to cover the scan / sustain electrode, the common sustain electrode, the first and the second trigger electrode, and the thickness of the first and second trigger electrode side than the scan / sustain electrode and the common sustain electrode side. A plasma display panel comprising a dielectric layer having a low dielectric constant.