JPH10207399A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To thin a liquid crystal display device and eliminate reinforcing rubber without injuring adhesive strength by inserting a flexible printed circuit board into a gap between a liquid crystal display panel and a frame covering the peripheral edge of the liquid crystal display panel after bending it. SOLUTION: Output part and input part of a liquid crystal driving LSI 3 are directly connected onto the conductor part of the peripheral edge surface of the liquid crystal display panel 1 by thermocompression through anisotropic conductive adhesive 2, and the flexible printed circuit board 8 made of polyimide resin is inserted into the gap formed by the liquid crystal display panel 1 and the frame 6 covering the peripheral edge of the liquid crystal display panel 1 after being bent to an S shape. Further, one end part 9 of the flexible printed circuit board 8 bent to the S shape is connected similarly onto the conductor part of the peripheral edge surface of the liquid crystal display panel 1 through the anisotropic conductive adhesive 2 by the thermocompression, and the other end part 10 of the flexible printed circuit board 8 is abutted on the inner surface of the frame 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device in which a flexible printed circuit board is connected to a peripheral surface of a liquid crystal display panel.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices have been further advanced in terms of low voltage driving, low power consumption, thinness and light weight, etc. as compared with conventional display devices, and have been used in many electric products including AV and OA equipment. ing.

In general, in a liquid crystal display device, a semiconductor element (a liquid crystal driving LSI) is provided on a terminal conductor of a liquid crystal display panel.
There are many different ways to implement
As a mounting method of a liquid crystal driving LSI in a liquid crystal display device, TAB (Tape Automated Bondi) is used.
ng) and a COG (Chip On Glass) method are known.

In the TAB method, an input / output connection portion of an LSI for driving a liquid crystal is connected to a film carrier by an ILB (Inner).
Lead Bonding) and OLB (Outer
In order to perform Lead Bonding, the connection between the film carrier and the printed circuit board is connected with solder and an anisotropic conductive adhesive, and the connection between the film carrier and the liquid crystal display panel is connected via an anisotropic conductive adhesive. This method is generally connected to terminal conductors of a liquid crystal display panel, but has the disadvantage that the outer shape of the product becomes large.

[0005] On the other hand, in the COG method, a liquid crystal driving LSI is directly mounted on a conductor on the peripheral surface of the liquid crystal display panel via an anisotropic conductive adhesive.
The output part and the input part of I are directly connected to the conductor on the peripheral surface of the liquid crystal display panel, and the flexible printed circuit is connected to the conductor on the peripheral surface of the liquid crystal display panel via an anisotropic conductive adhesive. Accordingly, a method of connecting a flexible printed circuit board to an input portion of a liquid crystal driving LSI is generally used, and the outer shape of the product can be smaller than that of the TCP method.

FIG. 2 shows an example of a typical partial sectional side view of a liquid crystal display device in which a liquid crystal driving LSI is mounted by using the above-mentioned conventional COG method. The output section and the input section of the liquid crystal driving LSI 3 are directly connected to the conductor section via the anisotropic conductive adhesive 2.
The flexible printed circuit board 4 is also the liquid crystal display panel 1
The flexible printed circuit board 4 is bent at the end of the liquid crystal display panel 1 into a U-shape, and the end 5 is connected to the liquid crystal display. The upper surface of the flexible printed circuit board 4 which is superimposed on the back surface of the panel 1 and connected to the conductor on the peripheral surface of the liquid crystal display panel 1 is provided between the flexible printed circuit board 4 and the frame 6 which covers the peripheral edge of the liquid crystal display panel 1. And is fixed by the reinforcing rubber 7.

[0007]

However, in the structure of the above-mentioned conventional liquid crystal display device, the flexible printed circuit board 4 is not provided.
Are connected to the liquid crystal display panel 1 via an anisotropic conductive adhesive 2 and are mounted in a U-shape, so that they are reinforced to increase the adhesive strength between the liquid crystal display panel 1 and the flexible printed circuit board 4. Rubber 7 or reinforcing resin is required,
Mounting man-hours were required. Further, since the end portion 5 of the flexible printed circuit board 4 is overlapped on the back surface of the liquid crystal display panel 1, there is a problem that the thickness of the liquid crystal display device is increased.

The present invention solves the above-mentioned conventional problems and provides a liquid crystal display device which can be made thinner without impairing the adhesive strength between a liquid crystal display panel and a flexible printed circuit board, and which can reduce the number of mounting steps. It is intended to provide.

[0009]

In order to achieve this object, a liquid crystal display device according to the present invention comprises a flexible printed circuit board connected to a peripheral surface of a liquid crystal display panel, a liquid crystal display panel, and a liquid crystal display panel. It is configured to be bent and inserted into a gap with the frame to be covered.

[0010] Thus, the thickness of the liquid crystal display device can be reduced, and the reinforcing rubber can be eliminated without deteriorating the adhesive strength to the liquid crystal display panel, and the number of mounting steps can be reduced.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention provides a flexible printed circuit board connected to the peripheral surface of a liquid crystal display panel, comprising a liquid crystal display panel and a frame covering the peripheral edge of the liquid crystal display panel. A liquid crystal display device that is configured to be bent and inserted into a gap, can maintain the connection strength between the liquid crystal display panel and the flexible printed circuit board by the elastic force of the bent flexible printed circuit board itself, and can be connected to the end of the flexible printed circuit board. Does not overlap with the back surface of the liquid crystal display panel, so that the liquid crystal display device can be made thinner, and the number of mounting steps can be reduced by eliminating the reinforcing rubber.

According to a second aspect of the present invention, a flexible printed circuit board connected to a peripheral surface of a liquid crystal display panel is provided with an S-shape in a gap between the liquid crystal display panel and a frame covering the peripheral edge of the liquid crystal display panel. This is a liquid crystal display device that is configured to be bent and inserted into a mold. The elastic force of the flexible printed circuit board that is bent into an S-shape can maintain the connection strength between the liquid crystal display panel and the flexible printed circuit board. Since the edge of the printed circuit board does not overlap with the back surface of the liquid crystal display panel, the liquid crystal display device can be made thinner, and the number of mounting steps can be reduced by eliminating the reinforcing rubber.

According to a third aspect of the present invention, there is provided the liquid crystal display device according to the first or second aspect, wherein a polyimide resin is used as a material of the flexible printed circuit board. Using elasticity,
The liquid crystal display device can be made thinner without impairing the connection strength between the liquid crystal display panel and the flexible printed board.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment) FIG. 1 is a partial cross-sectional view of a liquid crystal display device according to an embodiment of the present invention. The same components as those in FIG. The output part and the input part of the liquid crystal driving LSI 3 are directly connected to the conductor part on the peripheral surface of the liquid crystal display panel 1 through the anisotropic conductive adhesive 2 by thermocompression bonding. , One end of a flexible printed circuit board 8 bent into an S-shape and inserted into a gap formed by the liquid crystal display panel 1 and a frame 6 covering the periphery of the liquid crystal display panel 1. 9 is connected to the conductor on the peripheral surface of the liquid crystal display panel 1 by thermocompression bonding via the anisotropic conductive adhesive 2, and the other end 10 of the flexible printed circuit board 8 contacts the inner surface of the frame 6. I have.

In the liquid crystal display device having the above-mentioned structure, the flexible printed circuit board 8 made of polyimide resin is bent into an S-shape in a gap formed by the liquid crystal display panel 1 and the frame 6 covering the periphery of the liquid crystal display panel 1. The end 9 of the flexible printed circuit board 8 has no elasticity due to the elasticity of the polyimide resin.
And the other end portion 10 of the flexible printed circuit board 8 does not overlap with the back surface of the liquid crystal display panel 1 unlike the conventional example.
The liquid crystal display device can be thin because it is folded and folded in the gap where the reinforcing rubber was inserted in the conventional example.

[0016]

As described above, according to the present invention, the mounting structure of the flexible printed circuit board is constructed such that the flexible printed circuit board is bent and inserted into the gap between the liquid crystal display panel and the frame. Advantageously, the liquid crystal display device can be made thinner without impairing the connection strength with the flexible printed circuit board, and the number of mounting steps can be reduced by removing the reinforcing rubber.

[Brief description of the drawings]

FIG. 1 is a partial side sectional view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a partial side sectional view of a conventional liquid crystal display device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 liquid crystal display panel 2 anisotropic conductive adhesive 3 liquid crystal driving LSI 4, 8 flexible printed circuit board 5 end of flexible printed circuit board 6 frame 7 reinforcing rubber 9 one end of flexible printed circuit board 10 10 flexible printed circuit board 8 Other end

Claims (3)

[Claims] 1. A liquid crystal display device, wherein a flexible printed circuit board connected to the peripheral surface of a liquid crystal display panel is bent and inserted into a gap between the liquid crystal display panel and a frame covering the peripheral edge of the liquid crystal display panel. 2. A flexible printed circuit board connected to a peripheral surface of a liquid crystal display panel is provided in a gap between the liquid crystal display panel and a frame covering the peripheral edge of the liquid crystal display panel.
A liquid crystal display device configured to be bent and inserted into a character shape. 3. The liquid crystal display device according to claim 1, wherein a polyimide resin is used as a material of the flexible printed circuit board.