KR100348964B1 - Plasma Display Panel inserted Floating Electrode - Google Patents

Abstract

The present invention relates to a plasma display panel in which a floating electrode is inserted to improve luminance.

The plasma display panel in which the floating electrode is inserted includes a scan / sustain electrode and a common sustain electrode formed on an upper substrate, first and second trigger electrodes formed side by side between the scan / sustain electrode and the common sustain electrode, and a first And a floating electrode formed parallel to the first and second trigger electrodes between the second trigger electrodes.

With this configuration, the plasma display panel in which the floating electrode of the present invention is inserted can improve luminance by minimizing the intensity of discharge between the trigger electrodes.

Description

Plasma Display Panel inserted Floating Electrode

The present invention relates to a plasma display panel in which a floating electrode is inserted, and more particularly, to a plasma display panel in which a floating electrode is inserted to improve luminance.

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 three-electrode AC surface discharge type PDP.

Referring to FIG. 1, a discharge cell of a conventional three-electrode AC surface discharge type PDP includes a scan / sustain electrode 12Y and a common sustain electrode 12Z formed on an upper substrate 10, and a lower substrate 18. The formed 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 causing 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 generate 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. In order to solve this problem, a 5-electrode AC surface discharge type PDP as shown in FIG. 2 has been proposed.

2 is a perspective view showing a discharge cell structure of a conventional 5-electrode AC surface discharge type PDP.

Referring to FIG. 2, the conventional 5-electrode AC surface discharge type PDP is positioned at the edges of the discharge cells and the first and second trigger electrodes 34Y and 34Z formed on the upper substrate 30 to be positioned at the center of the discharge cells. 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 The address electrode 42X is formed in the center of the lower substrate 40 in the 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 at 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 an alternating pulse during the sustain period, and then discharge is started between the trigger electrodes 34Y and 34Z. Used to maintain.

3 shows the upper substrate rotated 90 degrees relative 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.

In the conventional 5-electrode AC surface discharge type PDP, one frame 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 discharge is started between the first and second trigger electrodes 34Y and 34Z, a strong gap between the scan / sustain electrode 32Y and the common sustain electrode 32Z is caused by the priming effect of the charged particles generated at this time. Disruption is 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. In this way, the discharge is initiated using the trigger electrodes 34Y and 34Z formed at a narrow interval Ni, thereby suppressing the increase of the discharge start voltage, but by the priming effect, the scan / sustain electrode 32Y and the common sustain electrode ( 32Z) may cause long sustain discharge in the discharge path. Thus, the amount of ultraviolet rays is increased, and the light emitting area is increased to improve the light emitting efficiency.

In the five-electrode PDP operating in this manner, fine discharge should occur between the trigger electrodes 34Y and 34Z. However, a strong discharge occurs between the trigger electrodes 34Y and 34Z formed at narrow intervals Ni. As such, when a strong discharge occurs between the trigger electrodes 34Y and 34Z, the discharge between the scan / sustain electrode 32Y and the common sustain electrode 32Z becomes weak. When a weak discharge occurs between the scan / sustain electrode 32Y and the common sustain electrode 32Z, the amount of ultraviolet light that excites the phosphor is reduced. Thus, the amount of ultraviolet light generated from the phosphor is reduced. That is, in the conventional 5-electrode PDP, strong discharge occurs between the trigger electrodes 34Y and 34Z, so that the luminance of the PDP is reduced.

Accordingly, an object of the present invention relates to a plasma display panel in which a floating electrode is inserted to improve luminance.

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

2 is a perspective view showing a discharge cell structure of a conventional 5-electrode AC surface discharge plasma display panel.

3 is a cross-sectional view illustrating a discharge cell structure of the 5-electrode AC surface discharge plasma display panel shown in FIG. 2.

4 is a cross-sectional view showing a discharge cell structure of an AC surface discharge plasma display panel according to an embodiment of the present invention.

5 is a diagram illustrating a voltage of a floating electrode represented by a voltage applied to the trigger electrodes shown in FIG. 4.

FIG. 6 illustrates wall charges formed in the dielectric layer when a waveform is applied to the trigger electrodes shown in FIG. 4. FIG.

<Description of Symbols for Main Parts of Drawings>

10,30: upper substrate 12Y, 32Y, 52Y: scan / sustain electrode

12Z, 32Z, 52Z: common sustain electrode 14, 22, 36, 44, 58, 70: dielectric layer

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

20X, 42X, 64X: Address electrode 24, 46, 60: Bulkhead

26,48,62 phosphor layer 34Y, 34Z, 54Y, 54Z trigger electrode

56: floating electrode

In order to achieve the above object, a plasma display panel in which the floating electrode of the present invention is inserted includes first and second scan and sustain electrodes and a common sustain electrode formed on an upper substrate, and first and second electrodes formed side by side between the scan and sustain electrodes and the common sustain electrode. And a floating electrode formed between the trigger electrode and the first and second trigger electrodes in parallel with the first and second trigger electrodes.

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. 4 to 6.

4 shows the upper substrate rotated 90 degrees relative to the lower substrate to show all the electrode structures in one discharge cell.

4 is a view showing a discharge cell of the PDP according to the first embodiment of the present invention.

Referring to FIG. 4, the PDP according to the first embodiment of the present invention is formed at the edges of the discharge cells and the first and second trigger electrodes 54Y and 54Z formed in the upper dielectric layer 58 to be positioned at the center of the discharge cell. A floating electrode 56 formed between the scan / sustain electrode 52Y and the common sustain electrode 52Z formed on the upper dielectric layer 58 and the first and second trigger electrodes 54Y and 54Z so as to be positioned, and the lower dielectric layer On the surfaces of the address electrode 64X formed on the 70, the partition wall 60 formed at a predetermined height between the upper dielectric layer 58 and the lower dielectric layer 70, and the lower dielectric layer 70 and the partition wall 60. The phosphor layer 62 to be applied is provided. Compared to the conventional PDP, it can be seen that the floating electrode 56 is inserted between the trigger electrodes 54Y and 54Z in the present invention. The floating electrode 56 is inserted between the trigger electrodes 54Y and 54Z to reduce the discharge intensity between the trigger electrodes 54Y and 54Z. Referring to the role of the floating electrode 56 in detail, alternating pulses are alternately applied between the trigger electrodes 54Y and 54Z during the sustain period. If a pulse as shown in FIG. 5 is applied to the first trigger electrode 54Y, and the second trigger electrode 54Z maintains the base potential, the floating electrode 56 has the first trigger electrode 54Y and the second trigger electrode. An intermediate voltage of 54Z is induced. That is, the potential of the floating electrode 56 is determined by the voltages applied to the first and second trigger electrodes 54Y and 54Z. The voltage of the floating electrode 56 is lower than the voltage applied to the first trigger electrode 54Y. Accordingly, as shown in FIG. 6, negative wall charges are formed on the first trigger electrode 54Y side, and positive wall charges are formed on the floating electrode 56. In addition, the voltage of the floating electrode 56 is higher than the voltage applied to the second trigger electrode 54Z. Accordingly, positive wall charges are formed on the second trigger electrode 54Z side, and negative wall charges are formed on the floating electrode 56. That is, the floating electrode 56 serves to reduce the intensity of discharge generated between the first and second trigger electrodes 54Y and 54Z. As described above, when a weak discharge occurs between the first and second trigger electrodes 54Y and 54Z, a strong discharge occurs between the scan / sustain electrode 52Y and the common sustain electrode 52Z. Therefore, a large amount of ultraviolet rays excite the phosphor, and a lot of visible light is generated from the phosphor, thereby improving the brightness of the PDP. The floating electrode 56 according to the embodiment of the present invention is formed to be 2/3 or less of the trigger electrodes 54Y and 54Z to minimize the gap between the first and second trigger electrodes 54Y and 54Z.

As described above, according to the plasma display panel in which the floating electrode is inserted, the floating electrode may be inserted between the trigger electrodes to minimize the intensity of discharge between the trigger electrodes, thereby improving luminance. 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 (3)

A scan / sustain electrode and a common sustain electrode formed on the upper substrate; First and second trigger electrodes formed side by side between the scan / sustain electrode and the common sustain electrode; And a floating electrode formed between the first and second trigger electrodes in parallel with the first and second trigger electrodes. The method of claim 1, And the floating electrode is formed to have a width narrower than the width of the first and second trigger electrodes. The method of claim 2, And the floating electrode is formed to have a width equal to or less than two thirds of the first and second trigger electrodes.