KR20080004781A - Plasma display device - Google Patents

Abstract

A plasma display apparatus is provided to implement a high adhesive structure and moisture transpiration resistance enforcing structure of an anisotropic conductive film by forming an end of the anisotropic conductive film longer than that of a substrate. A plasma display panel(11) has electrodes(12) between both substrates(111) to realize an image. A chassis base is attached to the plasma display panel. The chassis base supports the plasma display panel. A printed circuit board assembly is mounted on the chassis base. A flexible circuit(27) connects the printed circuit board assembly to the electrodes. An anisotropic conductive film(29) is connected to the electrode. The anisotropic conductive film electrically connects an electrode terminal(112) to a terminal(127) between the electrode terminal being withdrawn out of a dielectric(21) covering the electrode and the terminal formed on the flexible circuit. The anisotropic conductive film attaches the flexible circuit to the substrate. The anisotropic conductive film covers the electrode terminal and the substrate of the electrode terminal side. The anisotropic conductive film is formed longer than the end of the substrate.

Description

Plasma Display Device {PLASMA DISPLAY DEVICE}

1 is a perspective view schematically illustrating an exploded view of a plasma display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

3 is a front view seen from the front of the plasma display panel.

4 is an exploded perspective view of the plasma display panel, the anisotropic conductive film and the flexible circuit.

5 is a cross-sectional view of a state of use of the anisotropic conductive film.

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

11: plasma display panel 111: substrate

12: address electrode 21: dielectric layer

112: electrode terminal 13: heat dissipation sheet

14 double-sided tape 15 chassis base

15a: reinforcement part 115a, 215a: first and second bent parts

17: printed circuit board assembly 117: holding board assembly

217: scanning board assembly 317: address buffer board assembly

417: Image Processing / Control Board Assembly

517: power board assembly 18: boss

19, 33: set screw 27: flexible circuit

127 terminal 29 anisotropic conductive film

129: conductive portion 229: sealing portion

229a: first sealing part 229b: second sealing part

229c: extension 39: reinforcing member

25 driver integrated circuit 31 cover plate

34: thermal grease 35: thermal conductive sheet

36: alignment mark

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device, and more particularly, to form a high adhesion structure and a moisture permeable reinforced structure of an anisotropic conductive film electrically connecting an electrode terminal of a plasma display panel and an electrode of a flexible circuit. It relates to a plasma display device.

In general, a plasma display device is a visible light of red (R), green (G) and blue (B) generated by exciting the phosphor by using a vacuum ultraviolet (VUV: Vacuum Ultra-Violet) emitted from the plasma obtained through gas discharge A plasma display panel for implementing an image, a chassis base for supporting the plasma display panel, and a plurality of printed circuit board assemblies mounted to the chassis base are included.

The plasma display panel has two glass substrates facing each other, and a discharge space is formed therein, and thus has a weak mechanical rigidity against impact. Therefore, the chassis base is formed of a metal material having a greater mechanical rigidity than the glass substrate in order to support the plasma display panel.

In addition to supporting the mechanical rigidity of the plasma display panel, the chassis base provides a mounting space for printed circuit board assemblies, a heat sink function of the plasma display panel, and electro magnetic interference (EMI). It is responsible for the grounding function.

In addition, a plasma display panel is attached to the front surface of the chassis base via double-sided tape so that the chassis base performs the above functions, and printed circuit board assemblies are mounted on the rear surface of the chassis base.

The back of the chassis base has a plurality of bosses, which are mounted on the boss and fixedly mounted by fastening a set screw to the boss.

These printed circuit board assemblies are provided in plural to perform the respective functions of driving the panel. That is, the printed circuit board assemblies include a sustain board assembly for controlling the sustain electrode, a scan board assembly for controlling the scan electrode, an address buffer board assembly for controlling the address electrode, and a control signal for driving the address electrode by receiving an image signal from the outside. An image processing / control board assembly for generating a control signal required for driving the sustain electrode and the scan electrode and applying the same to the corresponding board assemblies, and a power board assembly for supplying power for driving the board assemblies.

The holding board assembly is connected to the sustain electrode which is drawn out from the inside of the plasma display panel, the scan board assembly is connected to the scan electrode which is drawn out from the inside of the plasma display panel, and the address buffer board assembly is moved from the inside of the plasma display panel to the outside. The address electrodes to be drawn out are connected through flexible printed circuits and connectors, respectively.

The flexible circuit connecting the address buffer board assembly and the address electrode forms a driver integrated circuit package (eg, a tape carrier package (TCP)). The driver integrated circuit package is formed by mounting a driver integrated circuit in a flexible circuit that generates an address pulse on the address electrode.

The driver integrated circuit package is connected to the long side of the plasma display panel having a long side and a short side, and is bent into a substantially "U" shape to be connected to the address buffer board assembly.

To this end, the address electrode has an electrode terminal exposed to the back substrate of the glass substrate, the driver integrated circuit package is connected to the electrode terminal of the address electrode via an anisotropic conductive film (ACF) at its terminals Connected.

In addition, the sustain electrode and the scan electrode have electrode terminals of a bus electrode formed on the front substrate of the glass substrate and exposed to the outside, and the terminals of the flexible circuit are connected to the electrode terminals of the bus electrode via an anisotropic conductive film. .

To this end, an anisotropic conductive film is placed on the electrode terminal. At this time, one line of the anisotropic conductive film corresponds to the end line of the dielectric layer covering the electrode (the above-mentioned address electrode, sustain electrode or scan electrode) of the plasma display panel. In addition, the other line of the anisotropic conductive film is placed on the electrode terminal while leaving the electrode terminal by a predetermined length at the end of the substrate. That is, the anisotropic film is placed on the electrode terminal with a part of the electrode terminal exposed.

In this state, the electrodes of the flexible circuit (or driver integrated circuit package) are placed on the anisotropic conductive film so as to face the electrode terminals. And the flexible circuit is crimped | bonded to the electrode terminal using an anisotropic conductive film as a medium. At this time, the anisotropic conductive film line at the end of the substrate coincides with the end of the electrode terminal.

In addition, the conductive ball, which is a component of the anisotropic conductive film, electrically connects the electrode terminal of the plasma display panel and the terminal of the flexible circuit. The polymer part, which is another component of the anisotropic conductive film, is cured by heat to mechanically attach the substrate and the flexible circuit of the plasma display panel.

Therefore, after pressing, when the end lines of the anisotropic conductive film and the dielectric layer do not coincide, the electrode terminals at the ends of the substrate are not completely covered by the anisotropic conductive film and are exposed to the outside, thereby being affected by external air and moisture. In other words, it is difficult to form a strong insulating film between the electrode terminals.

In addition, electrode terminals, which are mostly made of Ag, exhibit low adhesion of the anisotropic conductive film during operation and migration of silver and peeling of electrode terminals due to fine pores generated in the polymer part during adhesion. Cause Therefore, the electrode terminals generate a short or open phenomenon.

An object of the present invention relates to a plasma display device for forming a high adhesion structure and a moisture-permeable reinforced structure of an anisotropic conductive film in a portion connecting an electrode terminal and an electrode of a flexible circuit.

According to an embodiment of the present invention, a plasma display apparatus includes a plasma display panel including electrodes between two substrates to implement an image, a chassis base to which the plasma display panel is attached and supported, and a printed circuit board mounted to the chassis base. An electrical circuit between the electrode terminal and the terminal between an assembly, a flexible circuit connecting the printed circuit board assembly and the electrodes, and an electrode terminal connected to the electrode and drawn out of the dielectric layer covering the electrode and a terminal formed in the flexible circuit. And an anisotropic conductive film connected to the substrate and attaching the flexible circuit to the substrate, wherein the anisotropic conductive film covers the electrode terminal and the substrate toward the electrode terminal and may be formed longer than the end of the substrate. .

The anisotropic conductive film may cover the dielectric layer covering the electrode terminal.

The anisotropic conductive film may include a conductive part facing the electrode terminal and a conductive part facing the electrode terminal, and a sealing part having a non-conductive property and a sealing property facing the substrate.

The sealing part may include a first sealing part attached to the dielectric layer covering the electrode terminal, and a second sealing part attached to the substrate around the end of the electrode terminal.

The second sealing part may include an extension part extending longer than the end of the substrate.

The extension part may be formed to extend longer than a length covering the dielectric layer of the first sealing part.

The anisotropic conductive film may cover the alignment mark provided on one side of the electrode terminals arranged at the end of the substrate.

The sealing part may be formed of a thermosetting epoxy resin or a room temperature curing epoxy resin.

The electrode may be formed as an address electrode, the circuit board assembly may be formed as an address buffer board for applying a voltage to the address electrode, and the flexible circuit may be formed as a tape carrier package.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted to clearly describe the present invention, and like reference numerals designate like elements throughout the specification.

1 is a perspective view schematically illustrating an exploded view of a plasma display device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

Referring to these drawings, the plasma display apparatus includes a plasma display panel 11, heat dissipation sheets 13, chassis base 15, and printed circuit board assemblies 17 that display an image using gas discharge. Include.

The heat dissipation sheets 13 may be provided on the rear surface of the plasma display panel 11 so as to conduct and diffuse heat generated in the plasma display panel 11 in a planar direction due to gas discharge.

The chassis base 15 is attached to the rear surface of the plasma display panel 11 with a double-sided tape 14 with the heat dissipation sheets 13 therebetween to support the plasma display panel 11.

The printed circuit board assemblies 17 are mounted on the rear surface of the chassis base 15 and configured to drive the plasma display panel 11 to be electrically connected to the plasma display panel 11 (not shown).

The plasma display apparatus mechanically supports the plasma display panel 11 and the printed circuit board assemblies 17 provided on both sides of the chassis base 15 so that the plasma display panel 11 can continuously display an image. As a result, the plasma display panel 11 and the printed circuit board assemblies 17 may be electrically connected to each other.

The plasma display panel 11 displays an image by using gas discharge. Embodiments of the present invention relate to a coupling relationship between the plasma display panel 11 and other components. A detailed description of the description will be omitted.

The plasma display panel 11 includes electrodes for gas discharge. The address electrode 12 is shown in FIG. 2, and the sustain electrode and the scan electrode are omitted.

In addition, the plasma display panel 11 generates heat during gas discharge, and more heat is generated when the number of sustain discharges is increased in a short time to increase luminance.

The heat radiation sheet 13 absorbs heat generated from the plasma display panel 11 to conduct and diffuse in the planar direction of the plasma display panel 11. The heat dissipation sheet 13 may be made of various materials such as acrylic heat dissipating material, graphite heat dissipating material, metal heat dissipating material, or carbon nanotube heat dissipating material.

The chassis base 15 is attached to the rear surface of the plasma display panel 11 with the double-sided tape 14 as an adhesive with the heat dissipation sheet 13 therebetween to support the plasma display panel 11. In addition, the chassis base 15 mounts the printed circuit board assemblies 17 on the opposite side of the plasma display panel 11 to support the printed circuit board assemblies 17.

As such, the chassis base 15 has a mechanical rigidity capable of supporting the plasma display panel 11 and the printed circuit board assemblies 17.

The printed circuit board assemblies 17 are placed in bosses 18 provided in the chassis base 15 in a plurality, and fixed by set screws 19 fastened to the bosses 18. In addition, the printed circuit board assemblies 17 may be divided into a plurality of parts so as to share and perform respective functions of driving the plasma display panel 11.

For example, the printed circuit board assemblies 17 may include a sustain board assembly 117 for controlling a sustain electrode (not shown), a scan board assembly 217 for controlling a scan electrode (not shown), and an address electrode ( The address buffer board assembly 317 for controlling 12) receives an image signal from the outside, generates a control signal for driving the address electrode 12 and a control signal for driving the sustain electrode and the scan electrode, and applies it to the corresponding board assemblies. An image processing / control board assembly 417, and a power board assembly 517 for supplying power for driving the board assemblies.

The sustain board assembly 117 is connected to the sustain electrode through a flexible circuit (not shown), the scan board assembly 217 is connected to the scan electrode through a flexible circuit (not shown), and the address buffer board assembly 317 is It is connected to the address electrode 12 through the flexible circuit 27.

Each electrode terminal 112 of the sustain electrode, the scan electrode, and the address electrode 12 is electrically connected between the terminals 127 of the flexible circuit 27 via the anisotropic conductive film 29.

3 and 4, the anisotropic conductive film 29 is attached to the electrode terminals 112 while covering the plurality of electrode terminals 112, and the substrate 111 around the ends of the electrode terminals 112. ) Is also attached. In addition, the anisotropic conductive film 29 covers the alignment mark 36 provided on one side of the electrode terminals 112 arranged at the end of the substrate 111 together with the electrode terminals 112.

In connection with the present invention, the connection structure of the sustain electrode and the scan electrode and the flexible circuit is the same as that of the address electrode 12 and the flexible circuit 27. Accordingly, as shown in FIG. 2, the connection structure of the address electrode 12 and the flexible circuit 27 will be described.

For example, the flexible circuit 27 is formed of a tape carrier package (TCP) type in which a driver integrated circuit 25 for generating a control signal applied to the address electrode 12 is mounted.

Referring to FIG. 5, the anisotropic conductive film 29 includes a conductive portion 129 and a sealing portion 229. The conductive portion 129 is formed conductively in a portion facing the electrode terminal 112 of the address electrode 12 and the terminal 127 of the flexible circuit 27. The conductive portion 129 includes scattered conductive balls 129b. When the anisotropic conductive film 29 is compressed, the conductive balls 129b are formed of the electrode terminal 112 of the address electrode 12 and the flexible circuit 27. Is electrically connected to the terminal 127.

The sealing unit 229 is formed with a non-conductive property and a sealing property at a portion facing the substrate 111 at a position away from the electrode terminal 112. In addition, the sealing portion 229 may include a first sealing portion 229a attached to the dielectric layer 21 covering the electrode terminal 112 and a second sealing portion attached to the substrate 111 around the end of the electrode terminal 112. It is formed of a portion 229b.

The anisotropic conductive film 29 covers the part where the electrode terminal 112 is located and the part which is not located in common.

The anisotropic conductive film 29 is electrically connected to the electrode terminal 112 of the address electrode 12 and the terminal 127 of the flexible circuit 27 by the conductive portion 129, the first sealing portion 229a ) Forms a sealing structure of the electrode terminal 112 at the dielectric layer 21 side, and the second sealing portion 229b forms a sealing structure of the electrode terminal 112 at the end of the electrode terminal 112. That is, one anisotropic conductive film 29 forms a conductive structure and integrally forms a sealing structure on both sides of the electrode terminal 112.

The anisotropic conductive film 29 is formed on both sides of the dielectric layer 21 and the substrate 111 by the first sealing portion 229a and the second sealing portion 229b, that is, both sealing structures formed while being attached to the electrode terminal 112. The integrally attached structure forms a rigid attachment structure.

In addition, the second sealing portion 229b further includes an extension portion 229c. The extension part 229c extends longer than the end of the substrate 111 to increase the margin for forming the sealing structure of the electrode terminal 112 at the end of the substrate 111.

For example, the first sealing portion 229a is attached to the dielectric layer 21 in an inclined state without being parallel to the end of the dielectric layer 21 so that the second sealing portion 229b does not completely cover the end of the substrate 111. If not, the extension 229c may cover the substrate 111 to the end.

In this case, the end of the extension part 229c may not be in parallel with the end of the substrate 111 and may be inclined. That is, even when the end portion of the substrate 111 of the anisotropic conductive film 29 does not coincide with the end of the substrate 111, the extension part 229c completely covers the electrode terminals 112 to form a sealing structure.

In addition, when the anisotropic conductive film 29 is attached side by side with the end of the substrate 111 as shown in Figure 3, the length (L1) of the extension portion 229c extending from the end of the substrate 111 is the first The sealing portion 229a is formed longer than the length L2 covering the dielectric layer 21.

Therefore, the anisotropic conductive film 29 having the extension part 229c effectively strengthens the moisture permeability resistance that is weak at the end of the substrate 111 rather than the dielectric layer 21 side.

The sealing portion 229 is formed of a thermosetting epoxy resin or a room temperature curing epoxy resin, and has a strong property against the penetration of moisture. The anisotropic conductive film 29 as described above may be provided in plurality, such as a flexible circuit 27 facing the predetermined number of electrode terminals 112.

Meanwhile, the chassis base 15 may be formed by pressing a thin metal plate. In this case, it is preferable that the chassis base 15 has a reinforcing member 39 on its rear surface. This reinforcing member 39 reinforces the mechanical rigidity of the chassis base 15 to withstand torsional and bending forces.

In addition, the chassis base 15 is formed in a rectangular shape having a long side and a short side. This chassis base 15 is provided with the reinforcement part 15a bent at the long side. This reinforcement part 15a is equipped with the 1st bending part 115a and the 2nd bending part 215a, and forms the long side side edge of the chassis base 15. As shown in FIG. The first bent part 115a is bent to the opposite side of the plasma display panel 11 at the long side end of the chassis base 15. The second bent portion 215a is bent to be parallel to the plasma display panel 11 after the first bent portion 115a.

The cover plate 31 is mounted to the second bent portion 215a with a set screw 33. The driver integrated circuit 25 and the portion of the flexible circuit 27 around it are disposed between the second bent portion 215a and the cover plate 31. A thermal grease 34 is interposed between the second bent portion 215a and the flexible circuit 27, and a thermal conductive sheet 35 is interposed between the cover plate 31 and the flexible circuit 27. Each of the thermal grease 34 and the thermal conductive sheet 35 dissipates heat generated in the driver integrated circuit 25 and the flexible circuit 27 by the second bent portion 215a and the cover plate 31, respectively.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

As described above, according to the plasma display device according to the present invention, the terminal of the flexible circuit connected to the printed circuit board assembly and the electrode terminal of the plasma display panel are electrically connected to each other by anisotropic conductive film, and the ends of the anisotropic conductive film are connected. Is formed longer than the end of the substrate, there is an effect of forming a high adhesion structure and a moisture-permeable reinforced structure of the anisotropic conductive film in this connection portion.

Claims (12)

A plasma display panel including electrodes between both substrates to implement an image; A chassis base to which the plasma display panel is attached and supported; A printed circuit board assembly mounted to the chassis base; A flexible circuit connecting the printed circuit board assembly and the electrodes; And An anisotropic conductive film electrically connecting the electrode terminal and the terminal between an electrode terminal connected to the electrode and drawn out of the dielectric layer covering the electrode and a terminal formed in the flexible circuit, and attaching the flexible circuit to the substrate. Include, The anisotropic conductive film, A plasma display device covering the electrode terminal and the substrate toward the electrode terminal and longer than an end of the substrate. According to claim 1, The anisotropic conductive film covers the dielectric layer covering the electrode terminal. According to claim 1, The anisotropic conductive film, A conductive part having conductivity facing the electrode terminal; And a sealing part facing the substrate and having a non-conductive property and a sealing property. The method of claim 3, wherein The sealing unit, A first sealing part attached to the dielectric layer covering the electrode terminal; And a second sealing portion attached to the substrate around the end of the electrode terminal. The method of claim 4, wherein And the second sealing part includes an extension part extending longer than an end of the substrate. The method of claim 5, And the extension portion extends longer than a length covering the dielectric layer of the first sealing portion. According to claim 1, The anisotropic conductive film covers an alignment mark provided on one side of the electrode terminals arranged at the end of the substrate. The method of claim 3, wherein And the sealing part is formed of a thermosetting epoxy resin. The method of claim 3, wherein The sealing unit is a plasma display device formed of a room temperature curing epoxy resin. According to claim 1, And the electrode is formed of an address electrode. The method of claim 10, And the circuit board assembly is formed of an address buffer board for applying a voltage to the address electrode. The method of claim 11, wherein The flexible circuit is a plasma display device formed of a tape carrier package.

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