JP2001296815A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device which is improved in the reliability of wire bonding. SOLUTION: A driving IC 15 is disposed near the end of a lower glass substrate 3 of a display panel 20 composed of two sheets of counter substrates of the liquid crystal display device 19 and the lower glass substrate 3 is provided with a circuit board 21 in juxtaposition. An electrode terminal on the driving IC 15 and an electrode terminal 16 on the circuit board 21 are connected by a wire 18. After the liquid crystal panel 20 and the circuit board 21 are connected by the wire 18, the circuit board 21 is oppositely disposed on the non- display region 9 in such a manner that both terminals face each other. An insulative synthetic resin 34 is injected between the circuit board 21 and the lower glass substrate 3 and a spacer 25 having about the same thickness as the thickness of the upper glass substrate is inserted, by which the circuit board 21 is fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device in which a circuit board and a driving IC are provided for a display panel including a liquid crystal panel, a plasma display, an EL display, and the like.

[0002]

2. Description of the Related Art A display device comprises a liquid crystal panel, a plasma display, an EL display and the like. For example, a conventional liquid crystal display device 1 will be described with reference to FIGS.

FIG. 5 is a plan view of the liquid crystal display device 1, and FIG. 6 is an enlarged sectional view of a region A shown in FIG.

As shown in FIG. 6, in a liquid crystal display device 1, a liquid crystal 4 is interposed between an upper glass substrate 2 and a lower glass substrate 3 and further sealed with a sealing member 5, so that each of the glass substrates 2, 3 Transparent electrodes 6 and 7 for display are formed on each inner surface, and glass substrates are arranged so that the transparent electrodes 6 and 7 are orthogonal to each other to form a display area 8.

[0005] These display electrodes extend to the non-display area 9 in the transparent electrode 7, and in the transparent electrode 6, the lower glass substrate 3 is once passed through a conductive member provided between the two glass substrates 2 and 3. The light is transferred upward, and extends therefrom to the non-display area 9 of the lower glass substrate 3. On the transparent electrode 10 extended to the non-display area 9 of the lower glass substrate 3, the display electrode terminal 11 coated with a metal layer is formed.

On the lower glass substrate 3 of the liquid crystal panel 1, a circuit board 12 such as a printed circuit board is arranged in parallel so that respective end faces thereof are opposed to each other, and a metal plate 13 made of stainless steel or the like and an adhesive resin 14 are used. The lower glass substrate 3 and the circuit board 12 are fixed.

The driving IC 1 is mounted on the circuit board 12.
5 are arranged, and the electrode terminals of the driving IC 15 are the display electrode terminals 11 provided near the end of the lower glass substrate 3.
Each of the electrode terminals 16 provided on the circuit board 12 is connected to bonding terminals 17 and 18 made of gold, aluminum, or the like.

[0008]

However, in the liquid crystal display device 1 having the above structure, the lower glass substrate 3 and the circuit substrate 12 are merely fixed by the metal plate 13 via the adhesive resin 14. Therefore, the metal plate 13
When an impact or the like is applied in a direction perpendicular to the surface of the substrate, the adhesive strength of the adhesive resin 14 is reduced because the fixing strength in that direction is small, and the lower glass substrate 3 and the circuit substrate 12 are peeled off from the metal plate 13. As a result, there is a problem that the reliability of wire bonding is reduced.

Accordingly, an object of the present invention is to provide a connection between a display panel and a circuit board for inputting a display signal.
It is an object of the present invention to provide a display device in which durability against external impact is enhanced and reliability of wire bonding is improved.

[0010]

According to the present invention, there is provided a display device comprising:
An outer surface of one substrate of a display panel constituted by a plurality of opposing substrates is used as a display surface, and a driving IC for driving the display panel is disposed in a non-display area on an inner surface thereof. One electrode terminal group is formed with the provided electrode terminals, and the other electrode terminal group formed by arranging a plurality of electrode terminals on a circuit board on which input signal wiring for a driving IC is formed is formed. In a device configuration in which a terminal group and the other electrode terminal group are connected by wires, a circuit board is disposed on a non-display area of a display panel so that both electrode terminal groups face each other, and these display panel and circuit The circuit board is fixed with an insulating synthetic resin interposed between the board and the board.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a display device according to the present invention will be described with a liquid crystal display device. The liquid crystal display device 19 of the present invention is shown in FIGS.

FIG. 1 is a plan view of the liquid crystal panel, and FIG.
FIG. 3 is a schematic cross-sectional view showing a connection relationship with the circuit board 21, FIG. 3 is a schematic cross-sectional view of a region B in FIG. 1 viewed from an arrow b direction, and FIG. It is a side view. The same members as those of the conventional liquid crystal display device 1 are denoted by the same reference numerals.

As shown in FIG. 1, in a liquid crystal display device 19, two circuit boards 21 such as printed boards are arranged on opposite sides of a liquid crystal panel 20, and a circuit board 21 is provided on the other end of the liquid crystal panel 20. 22 are juxtaposed.

In this embodiment, the circuit board 21 shown in FIG.
The arrangement structure of the present invention will be described.

As shown in FIG. 2, in the liquid crystal panel 20 of the liquid crystal display device 19, a liquid crystal 4 is interposed between an upper glass substrate 2 which is a common side glass substrate and a lower glass substrate 3 which is a segment side glass substrate. , And sealed with a sealing member 5. Transparent electrodes 6 and 7 for display are formed on each inner surface of each of the glass substrates 2 and 3 so that the transparent electrodes 6 and 7 are orthogonal to each other. Each glass substrate is arranged to form a display area 8. The display electrode 7 extends to the non-display area 9 of the lower glass substrate 3, and the display electrode terminal 11 is formed thereon.

Further, a driving IC 15 is disposed near an end of the lower glass substrate 3, and an electrode terminal and a display electrode terminal 11 provided on an upper surface of the driving IC 15 are bonded to bonding wires 17 made of gold, aluminum, or the like. It is connected with.

The electrode terminals 16 are formed on the circuit boards 21 arranged on the opposite sides of the liquid crystal panel 20 respectively.
The electrode terminals 16 are connected to the electrode terminals of the driving IC 15 by bonding wires 18 made of gold, aluminum, or the like.
It is movable with respect to.

Therefore, in the above configuration, as shown in FIG. 3, the bonding wire 18 is bent so that the electrode terminal of the driving IC 15 and the electrode terminal 16 provided on the circuit board 21 face each other. It can be arranged in the non-display area 9 of the liquid crystal panel 20.

When disposing the circuit board 21 on the non-display area 9, the circuit board 21 and the upper glass substrate 2 of the liquid crystal panel 20 are temporarily fixed with an adhesive resin 23 such as a double-sided tape.

In this temporary fixing, a double-sided tape is attached in advance to the end of the upper glass substrate 2 and the circuit board 2 is placed thereon.
This is performed by pasting the ends of the sheets 1 so as to overlap each other. The double-sided tape used at this time only needs to have heat resistance.

The term "heat resistance" means that the adhesiveness is maintained within the guaranteed temperature of the liquid crystal panel, and that the display surface of the liquid crystal panel is not adversely affected by heat shrinkage or expansion.

Then, between the circuit board 21 and the lower glass substrate 3, an insulating synthetic resin 24 made of an epoxy resin, a silicon resin, or the like, which is not electrically energized, is injected and solidified.

Preferably, as shown in FIG. 4, a spacer 25 having a thickness substantially equal to the thickness of the upper glass substrate 2 of the liquid crystal panel 20 is inserted into an open space where no driving IC is provided. 21 are fixed.

The spacer 25 is made of, for example, metal,
Any material may be used as long as it is made of ceramics, synthetic resin, or the like, preferably has a coefficient of thermal expansion similar to that of the glass substrates 2 and 3 and has insulating properties.

The spacer 25 is installed on the end of the lower glass substrate 3 in advance by utilizing the viscosity of the insulating protective resin 24, so that the space between the circuit board 21 and the lower glass substrate 3 can be easily formed. Spacers 25 can be provided.

The circuit board 22 is provided in the same manner as the conventional circuit board 12 arrangement structure. That is, the lower glass substrate 3 and the circuit board 22 are arranged and fixed on the metal plate 13 made of stainless steel or the like and the adhesive resin layer 14.

Each of the circuit boards 21 and 22 has, for example, a multilayer wiring structure in which one or more wiring layers are formed inside the boards, and includes bus lines, power supplies, logic, etc. necessary for driving the driving IC 15. Or a multilayer board on which various power supplies and signal processing circuits supplied from the outside are mounted.

Thus, according to the liquid crystal display device 19 having the above structure, the circuit board 21 and the liquid crystal panel 20 are connected by the wire 18, and the circuit board 21 is disposed on the non-display area 9 of the liquid crystal panel 20 so as to be opposed to each other. By using the synthetic resin 24 and further attaching the spacer 25, the circuit board 21 is provided.
Is fixed, thereby eliminating the problem that the glass substrate 3 and the circuit board 21 are separated from the metal plate 13 as in the related art, and as a result, the wire bonding property is improved.

In addition, by disposing the circuit board 21, which is conventionally arranged in parallel with the lower glass substrate 3, on the non-display area 9 of the liquid crystal panel 20, the size of the device is reduced and the device is downsized.

Also, the applicant of the present application has already
In order to protect the bonding wires 5 and the bonding wires 17 and 18 from the external environment and impact, a technique of performing a hard coat process using an insulating synthetic resin has been proposed. The impact applied to the bonding wires 17 and 18 is mitigated by the circuit board 21 and the lower glass substrate 3, thereby eliminating the need for performing a hard coat process.

Therefore, a soft resin such as a silicon-based resin can be positively used as the insulating synthetic resin 24, whereby the distortion caused by the difference in the coefficient of thermal expansion between the circuit board 21 and the insulating synthetic resin 24 can be improved. However, the effect on the bonding wires 17 and 18 can be reduced, and the reliability of wire bonding can be improved.

In the present embodiment, the arrangement structure of the present invention has been described using the circuit board 21. However, the circuit board 22 is similarly arranged to face the non-display area 9 of the liquid crystal panel 20. Thereby, the operation and effect of the present invention can be obtained.

Further, in the liquid crystal display device 19 having the above configuration, the wires 1 connecting the circuit board 21 and the liquid crystal panel 20 are connected.
8 is preferably coated with an insulating protective resin, so that an electrical short-circuit (short-circuit) occurring between the wires 18 arranged at a narrow pitch can be prevented.

The resin for coating the wire is required to have a property of being flexible after coating and capable of following the bending property of the wire. Examples of such a resin include an epoxy resin and a silicon resin. There is.

To cover the wire with an insulating protective resin, the wire is coated by spraying,
Alternatively, it may be dipped. In the case of spraying by spraying, attach a spray nozzle to the tip of the robot arm and cover the area other than the area to be sprayed with a mask,
By moving the tip of the robot arm along the sprayed area, spraying can be performed as required.

In the case of the liquid crystal display device 19 having such a configuration, first, the wires 17 and 18 are coated with an insulating protective resin, and then the circuit board 21 is opposed to the non-display area 9 of the liquid crystal panel 20. Then, after temporarily fixing with an adhesive resin 23 or the like, an insulating synthetic resin 24 may be injected between the two substrates.

The insulating resin 2 interposed between the two substrates
4 is for covering the surface of the circuit board 21 and the lower glass substrate 3 after coating the wires 17 and 18 with an insulating protective resin.
An appropriate amount may be applied in advance on the surface near the edge on which the display electrode terminals 11 are formed, and then the circuit board 21 may be disposed to face the non-display area 9 of the liquid crystal panel 20.

It should be noted that the present invention is not limited to the above embodiment, and various changes and improvements may be made without departing from the scope of the present invention. For example, in this example, a liquid crystal panel was described as a display panel, but a plasma display and an E display were used as other display devices.
A similar effect can be obtained in a display panel such as an L display.

Further, in the above embodiment, both the insulating synthetic resin 24 and the spacer 25 are used. However, the present inventor does not provide the spacer 25 and only uses the insulating synthetic resin 24. It has been confirmed that the object of the present invention is sufficiently achieved.

[0040]

As described above, according to the display device of the present invention, the outer surface of one of the substrates of the display panel constituted by the two opposing substrates is used as the display surface, and the display is performed in the non-display area on the inner surface. An IC for driving the panel is arranged, and the electrode terminals provided on the upper surface of the driving IC constitute one electrode terminal group, and a plurality of electrode terminals are formed on a circuit board on which input signal wiring for the driving IC is formed. Are formed, and one electrode terminal group and the other electrode terminal group are connected by wires, and the circuit board is mounted on the display panel so that both electrode terminal groups face each other. The circuit board is fixed to the display area by facing each other, and an insulating synthetic resin and a spacer are interposed between the two boards. As a result, an external impact is not directly applied to the drive IC or the connection wire, and the problem that the glass substrate or the circuit board is peeled off from the metal plate as in the related art is eliminated. An enhanced and high quality display device could be provided.

Moreover, in the display device of the present invention, a metal plate for fixing a circuit board as in the prior art is not required, and the weight and cost can be reduced accordingly.

Further, in the prior art, since the portion covered with the driving IC and the bonding wire was exposed to the outer surface of the device, the shape of the entire device was unclear. Since the operation is performed between the circuit board and one of the substrates of the display panel, the shape of the entire device is clarified, and the housing capacity of the device is improved.

[Brief description of the drawings]

FIG. 1 is a plan view of a liquid crystal display device of the present invention.

FIG. 2 is a schematic cross-sectional view showing a connection relationship between a liquid crystal panel and a circuit board in a stage before the circuit board is disposed to face the liquid crystal display device of the present invention.

FIG. 3 is a schematic cross-sectional view of a region B in FIG. 1 as viewed from a direction of an arrow b.

FIG. 4 is a schematic side view of a region B in FIG. 1 as viewed from the direction of arrow c.

FIG. 5 is a plan view of a conventional liquid crystal display device.

FIG. 6 is an enlarged cross-sectional view of a region A in FIG. 5 as viewed from a direction of an arrow a.

[Explanation of symbols]

 1, 19 liquid crystal display device 2, 3, glass substrate 4, liquid crystal 5, sealing member 6, 7, transparent electrode 8 Display area 9 Non-display area 10 Transparent transparent electrode 11 Display electrode terminals 12, 21, 22 Circuit board 13 Metal plate 14, 23 Adhesive resin 15 Driving IC 16 Electrode terminal 17, 18 Bonding Wire for liquid crystal display 20 Liquid crystal panel 24 Insulating synthetic resin 25 Spacer

Continued on the front page F term (reference) 2H092 GA45 GA55 GA59 GA60 NA30 5E344 AA02 AA04 AA16 AA19 BB06 CD22 CD40 DD10 EE17 5G435 AA00 AA14 BB05 BB06 BB12 EE34 EE37 EE42 KK05 KK09 LL00

Claims (1)

[Claims] An outer surface of one substrate of a display panel composed of two opposing substrates is used as a display surface, and a driving IC for driving the display panel is disposed in a non-display area on an inner surface thereof.
One electrode terminal group is formed by electrode terminals provided on the upper surface of the driving IC, and the other electrode is formed by arranging a plurality of electrode terminals on a circuit board on which input signal wiring for the driving IC is formed. A display device in which a terminal group is formed and one electrode terminal group and the other electrode terminal group are connected by wires, and a circuit board is placed on a non-display area of a display panel so that both electrode terminal groups face each other. A display device, wherein the circuit board is fixed by interposing an insulating synthetic resin between the display panel and the circuit board.