KR20000066856A - Structure for Plasma Display Panel - Google Patents

Abstract

PURPOSE: A PDP structure is provided to reduce alignment error between pads of sustain electrodes and FPC or loss of panel from FPC breaking by constructing a contact connected with one ends of the sustain electrodes CONSTITUTION: A PDP is formed on a substrate(100) constituting the PDP. A number of sustain electrodes(110) are applied with sustain voltage for driving the PDP. A contact(120) is connected with the sustain electrodes(110) to transmit the sustain voltage to each of the sustain electrodes(110). A drive circuit(130) applies the sustain voltage to the contact(100). Even if some of the wiring is broken, the sustain electrodes(110) are connected with the contact(100) via other wiring that are not broken. The breaking of wiring does not give any effect to the sustain electrodes(110), and the PDP is normally operated even if the breaking takes place. Also, alignment with the FPC wiring is easier and error is reduced.

Description

Structure of Plasma Display Panel {Structure for Plasma Display Panel}

The present invention relates to a plasma display panel, and more particularly, to a structure of a plasma display panel in which a sustain electrode and a driving circuit are bonded.

Plasma display panels and liquid crystal displays (LCDs) are spotlighted as next generation display devices with the highest practicality among flat panel display devices. In particular, the plasma display panel has a higher luminance and wider viewing angle than a liquid crystal display device, and thus has wide applicability as a large, thin display such as an outdoor advertising tower, a wall display TV, or a theater display.

The plasma display panel emits the phosphor by irradiating the phosphor with ultraviolet rays generated by the discharge of the inert gas enclosed in the discharge cell.

In the typical three-electrode surface discharge plasma display panel, as shown in FIG. 1A, the upper substrate 10 and the lower substrate 20 installed to face each other are bonded to each other. FIG. 1B illustrates a cross-sectional structure of the plasma display panel illustrated in FIG. 1A, and the lower substrate 20 is rotated 90 ° for convenience of description.

The upper substrate 10 is composed of a pair of sustain electrodes, a dielectric layer 11 for applying the sustain electrodes, and a protective film 12. The lower substrate 20 has an address electrode 22 and an address electrode 22. The dielectric film 21 formed on the entire surface of the substrate including the dielectric film 21, the partition 23 formed on the dielectric film 21 between the address electrodes 22, and the surfaces of the partition 23 and the dielectric film 21 in each discharge cell. It is composed of a phosphor 24, the space between the upper substrate 10 and the lower substrate 20 is filled with an inert gas to form a discharge region.

The pair of sustain electrodes, that is, the scan electrode and the sustain electrode, are composed of transparent electrodes 16 and 16 'and a bus electrode made of metal as shown in FIGS. 2A and 2B to increase light transmittance of each discharge cell. have. 2A is a plan view of the sustain electrode and the scan electrode, and FIG. 2B is a cross-sectional view of the sustain electrode and the scan electrode. The bus electrode receives the discharge voltage from the driving IC installed outside, and the transparent electrodes 16 and 16 'receive the discharge voltage applied to the bus electrode to cause discharge between adjacent transparent electrodes. The total width of the sustain electrode is about 300 micrometers (µm), and the transparent electrodes 16 and 16 'are made of indium oxide or tin oxide, and the bus electrode is made of chromium (Cr) -copper (Cu) -chromium ( It consists of three layers of thin films consisting of Cr). At this time, the width of the bus electrode line is set to approximately 1/3 of the width of the sustain electrode line.

In the three-electrode surface discharge type AC plasma display panel, first, when a driving voltage is applied between the address electrode 21 and the scan electrode 25, an opposite discharge is generated between the address electrode 21 and the scan electrode 25. This causes wall charges on the surface of the protective layer 28 of the superstructure. When the discharge voltages having opposite polarities are continuously applied to the scan electrode 25 and the sustain electrode 26 and the driving voltage applied to the address electrode 21 is cut off, the scan electrode 25 and the scan electrode 25 are blocked by wall charge. A predetermined potential difference is maintained between the sustain electrodes 26 to cause surface discharge in the discharge regions on the surfaces of the dielectric layer 27 and the protective layer 28. As a result, ultraviolet rays are generated from the inert gas in the discharge region. The phosphor 24 is excited by the ultraviolet rays, and color display is performed by the emitted phosphor 24.

That is, while the electrons inside the discharge cell accelerate to the cathode (-) by the applied driving voltage, helium (He) is filled with the inert mixed gas filled with the pressure of about 400 to 500 torr in the discharge cell. As the main component, it collides with a Penning mixed gas to which xenon (Xe), neon (Ne) gas, etc. are added, and the inert gas is excited to generate ultraviolet rays having a wavelength of 147 nm. Such ultraviolet rays collide with the phosphor 24 surrounding the address electrode 21 and the partition 23 to emit light in the visible light region.

The plasma display panel discharges a cell constituting a pixel by controlling the application of voltage to the address electrode, the scan electrode, and the sustain electrode, and the amount of light emitted by the discharge determines the discharge time of the cell. Adjust by changing. In other words, the gray scale required for image display is realized by varying the length of time each cell is discharged within the time required to display the entire image (1/30 second in the case of NTSC TV signal). . At this time, the brightness of the screen is determined by the brightness when each cell is discharged to the maximum. In addition, in order to maximize the brightness of the plasma display panel screen, it is necessary to keep the discharge time of the cell as long as possible within the time necessary for constructing one screen.

FIG. 3 is a block diagram illustrating a schematic structure of a plasma display panel including a driving circuit, and shows a panel, an address electrode driver 60, a scan electrode driver 70, and a sustain electrode driver 80. The address electrode 21 formed in each cell of the plasma display panel is connected to the address electrode driver 60 to receive an address voltage, and the scan electrode 16 is connected to the scan electrode driver 70 to scan voltage. (scan voltage) is applied, and the sustain electrode 16 'is connected to the sustain electrode driver 80 to receive a sustain voltage.

The controller 90 of the plasma display panel driving circuit unit receives various control signals such as clock signals, RGB data, vertical synchronization signals, and horizontal synchronization signals from the outside, generates scan data, and applies the scan data to the scan electrode driver. Is generated and applied to the address electrode driver. Accordingly, the address electrode, the scan electrode, and the sustain electrode are driven in accordance with the signals applied to the respective drivers to display an image on the plasma display panel.

There are various ways of displaying an image by driving the plasma display panel, but a method commonly used is a subfield method.

In the subfield method, one screen is implemented by setting a screen displayed by discharge of a cell to one sub-screen, and controlling the scan electrode driver and the sustain electrode driver to overlap several sub-screens. In such a subfield method, a plurality of subpictures are sequentially gathered to form a single image. In this case, the number of subpictures is equal to the number of gradation bits of the image. That is, if the gray level of the image implemented on the screen is 8 bits, the number of subscreens implemented by the subfield method is 8 sheets. FIG. 4A illustrates a waveform applied to each electrode of the plasma display panel, and FIG. 4B illustrates a subfield type plasma display panel driving method showing a scanning order of each cell of the plasma display panel according to the waveform of FIG. 4A. .

First, the subfield method collects 8-bit digital video signals with bits of the same weight from MSB (Most Signal Bit) to LSB (Least Signal Bit), and then scans the MSB data on the plasma display panel for a predetermined T time. The lower bits are scanned for T / 2 time, T / 4 time, and T / 8 time in bit order close to the MSB, and LSB data is scanned for T / 128 time to form a sub picture. The subfield method implements 256 gray levels by using the afterimage effect of snow on the light emitted from each sub-screen.

At this time, in order to efficiently drive the high-resolution AC plasma display panel, the subfield method divides the plasma display panel screen into 8 zones as shown in FIG. Sub-screens are arranged in each zone to be as follows. Each sub-screen follows the ADS (Address and Display period Separate) method, which applies the application period of the address pulse and the application period of the sustain pulse separately.In the sub-picture layout of each zone, the address pulse and the sustain pulse are simultaneously applied. It follows the CAS (Concurrent Address-Sustain) method which allows it to be In general, one field is divided into 45 basic blocks.

However, in the structure of the conventional plasma display panel, although the same voltage pulse is applied to all of the sustain electrodes, the wiring 51 of the FPC is connected to each of the sustain electrode lines 16 'as shown in FIG. . This causes a problem that the alignment error between the pad of the sustain electrode 16 'and the FPC 50 is so small that the process of attaching the panel 10 and the FPC 50 becomes difficult. In addition, when a part of the wiring 51 provided in the FPC 50 is disconnected, the sustain voltage is not transmitted to the sustain electrode 16 ', which causes a problem in that the loss of the panel increases.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object thereof is to provide a structure of a plasma display panel which can reduce the amount of loss of the panel due to misalignment between the pad of the sustain electrode and the FPC or disconnection of the FPC wiring. .

FIG. 1A schematically illustrates a structure of a general surface discharge plasma display panel. FIG.

1B is a view schematically showing the structure of a discharge cell

2A and 2B schematically illustrate the structure of a sustain electrode.

3 is a block diagram illustrating a plasma display panel including a driving circuit unit.

4A is a diagram showing waveforms applied to each electrode of a plasma display panel.

Fig. 4B is a diagram showing a subfield plasma display panel driving method showing the scanning order of each discharge cell.

5 is a diagram illustrating an operation of a plasma display panel driven in a subfield method.

6 shows the structure of a conventional plasma display panel using an FPC.

7 shows an example of a plasma display panel according to the present invention;

8 is a view showing another example of a plasma display panel according to the present invention;

9 illustrates a plasma display panel in which wiring is disconnected.

Explanation of symbols for the main parts of the drawing.

100: substrate 100 ': display area

110: sustain electrode 120: contact

121: pad 130: drive circuit

140: FPC (Flexible Printed Circuit)

A: disconnected part

The structure of the plasma display panel according to the present invention is characterized by forming a contact point for commonly connecting one side of the sustain electrodes to be connected to the driving circuit.

The structure of the plasma display panel according to the present invention includes a plurality of sustain electrodes 110 and sustain electrodes formed in the display area 100 ′ on the substrate 100 to receive a sustain voltage as shown in FIG. 7. And a contact circuit 120 (not shown) for applying a sustain voltage to the contact 120 which is commonly connected to the 110 to transfer the sustain voltage to the commonly connected sustain electrode 110.

All the sustain electrodes 110 of the present invention are commonly connected to the contacts so that the sustain electrodes 110 are applied with the same voltage. In this case, the contact point is commonly connected to all the sustain electrodes 110 so as to transfer the sustain voltage output from the external driving circuit to each of the sustain electrodes 110. As shown in FIG. 8, a plurality of contacts 121, 122, 123, and 124 corresponding to each group are grouped by grouping all of the sustain electrodes 110 on the substrate 100 into several groups. It is preferable that it consists of.

In addition, the plasma display panel according to the present invention additionally includes an additional contact 120 for connecting all the sustain electrodes in common as shown in FIG. 7 in addition to the common contact formed in the driving circuit. Of course, the contact point 120 may be formed outside the display area 100 ′ of the substrate 100.

In the plasma display panel to which the additional contact 120 is added, a part of the sustain electrode 110 connected to the contact 120 or a grouping of electrodes such as pads 121, 122, 123, and 124 is illustrated in FIG. 9. Even if disconnected (A) as described above, it is possible to supply the sustain voltage to the sustain electrode 110 due to the other part grouping the electrodes.

In addition, the plasma display panel of the present invention is configured by additionally installing a flexible printed circuit (FPC) between the driving circuit (not shown) and the contact point 120 to smoothly supply the sustain voltage. good. The FPC serves to transfer the sustain voltage output from the driving circuit to the contact point 130.

Hereinafter, the operation principle of the plasma display panel according to the present invention will be described.

When the driving circuit generates a sustain voltage, the sustain voltage is transmitted to the contact point 120 through the FPC. Then, a sustain voltage is applied to each of the sustain electrodes 110 by the contact point 120 to operate the plasma display panel.

At this time, when a part of the FPC wiring or the wiring of the sustain electrode between the common contact and the FPC is disconnected (A), the current by the sustain voltage does not flow in the disconnected wiring, but the wiring which is not disconnected is connected to the contact 120. The sustain voltage continues to be transmitted. As a result, the operation of applying the sustain voltage to each sustain electrode 110 is not influenced at all, so that the plasma display panel operates normally.

In addition, since the number of the contacts 120 formed on the plasma display panel of the present invention is smaller than that of the conventional sustain electrode 110, there is room for forming the contact 120 larger than the pad of the sustain electrode 110 during the manufacturing process. have. Therefore, alignment with the FPC wiring is easier than alignment with a conventional pad, and there is little possibility that an error will occur.

The structure of the plasma display panel according to the present invention applies a sustain voltage to a contact point connected to a plurality of sustain electrodes to transfer the sustain voltage to the sustain electrodes. There is an effect to reduce. And even if a part of wiring is disconnected, since the wiring which is not disconnected is connected to a contact, the sustain voltage is transmitted to each sustain electrode irrespective of whether the wiring is disconnected. Therefore, there is an effect that the amount of loss of the panel due to poor wiring is reduced.

Claims (5)

In the plasma display panel, A plurality of sustain electrodes formed in the display area on the substrate constituting the plasma display panel; A contact point for commonly connecting one side of the plurality of sustain electrodes, and And a driving circuit electrically connected to the contact point. The method of claim 1, wherein the contact point And the sustain electrodes are composed of pad groups grouped into a plurality of groups and commonly connected to each group. The structure of a plasma display panel according to claim 2, further comprising a separate common contact for connecting all of the pad groups in common. The structure of claim 1, wherein the common contact is formed outside the display area of the substrate. The structure of a plasma display panel according to claim 1, further comprising a flexible printed circuit (FPC) for transmitting a sustain voltage output from the driving circuit to the common contact.