JP2004029651A - Liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure more mounting area for parts on a flexible substrate to be connected to the terminal part of a liquid crystal panel. <P>SOLUTION: In a liquid crystal display element in which the flexible substrate 20 connected to the terminal part 111 of the liquid crystal panel 10 is folded almost 180° and placed on the back side of the liquid crystal panel 100, a parts-mounting part 20B for surface-mounting chip parts 30 is formed in a folded part 21 of the flexible substrate. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a liquid crystal display device in which a flexible substrate is connected to a terminal portion of a liquid crystal panel, and more particularly to a technique for mounting components on the flexible substrate.
[0002]
[Prior art]
A flexible substrate such as a COF (chip on film) is connected to the liquid crystal panel. An example will be described with reference to FIG. 4. The liquid crystal panel 10 includes a pair of transparent electrode substrates 11 and 12 pressed together via a peripheral sealing material (not shown), and in this example, a terminal portion is provided on the transparent electrode substrate 11 on the observation surface side. 111 are continuously provided. In a transmission type or semi-transmission type model, a light guide plate 13 of a backlight is arranged on the back surface of the transparent electrode substrate 12 on the non-observation surface side (back surface side).
[0003]
One end of the flexible substrate 20 is connected to the terminal portion 111 via, for example, an anisotropic conductive adhesive film. In particular, since a liquid crystal display element used for a mobile phone or the like is required to be miniaturized, the flexible substrate 20 is bent by approximately 180 °, and the other end side is a back surface side of the transparent electrode substrate 12 on the non-observation surface side. Then, it is folded back to the back side of the light guide plate 13 of the backlight.
[0004]
In the case of COF, a bare chip or another chip component such as an IC or an LSI for driving a liquid crystal is mounted on the flexible substrate 20, but as the size of the liquid crystal panel 10 is reduced, the size of the flexible substrate 20 is also restricted. As a result, the component mounting area has become smaller.
[0005]
Therefore, in order to efficiently use the limited component mounting area of the flexible substrate 20, as shown in this example, a part of the flexible substrate 20 facing the terminal portion 111 in a state where the flexible substrate 20 is folded by approximately 180 ° is also used as the component mounting area 20A. However, due to the recent demand for more miniaturization, it is expected that the parts mounting area is still insufficient.
[0006]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to secure a new component mounting area in response to miniaturization of a flexible substrate connected to a liquid crystal panel.
[0007]
[Means for Solving the Problems]
In order to solve the above problem, the present invention includes a liquid crystal panel having a terminal portion, and a flexible substrate having one end connected to the terminal portion, wherein the flexible substrate is bent at approximately 180 ° to a predetermined portion thereof. A liquid crystal display element having a bent portion, wherein the other end of the flexible substrate is arranged on the non-observation surface side of the liquid crystal panel, a component for surface mounting a chip component on the bent portion of the flexible substrate. It is characterized in that the mounting part is formed, and according to this, the chip component can be mounted also on the bent part of the flexible substrate which is bent by approximately 180 °.
[0008]
Since the bent portion of the flexible substrate has a curved surface, in order to mount the chip component with good stability, a pair of cut-and-raised tongue pieces formed by a substantially U-shaped cut line are formed on the component mounting portion, It is preferable that the bases of the tongues are opposed to each other and arranged symmetrically with respect to the virtual bending line of the bent portion.
[0009]
In another aspect, a pair of cut-and-raised tongues formed by a substantially C-shaped cut line are formed on the component mounting portion, and the base portions of the tongues are formed along predetermined fold lines of the bent portion along predetermined fold lines. They may be arranged facing each other at intervals.
[0010]
In any case, a substantially flat surface appears at the bent portion of the flexible substrate due to the pair of cut-and-raised tongue pieces, so that the chip component can be mounted with high stability.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. The same reference numerals as those in the conventional example described in FIG.
[0012]
1, one end of the flexible substrate 20 is connected to the terminal portion 111 of the liquid crystal panel 10, the flexible substrate 20 is bent by approximately 180 °, and the other end is connected to the backlight 13 as in the conventional example described above with reference to FIG. In the present invention, a new component mounting portion 20B is provided in the bent portion 21 of the flexible substrate 20 which is bent by approximately 180 °, and the chip component 30 can be mounted in the bent portion 21 as well. Like that.
[0013]
FIG. 2 shows a first preferred embodiment of the component mounting section 20B. FIG. 2A is a diagram showing the state before the flexible substrate 20 is bent as viewed from the lower side in FIG. 1, and FIG. 2B is a right side view thereof. The XX line in the figure is a virtual bending line of the bending portion 21.
[0014]
The component mounting portion 20B is provided with a pair of cut-and-raised tongue pieces 23 and 24 that appear when the flexible substrate 20 is bent. Solder lands 231 and 241 for soldering the chip component 30 are formed on each of the cut and raised tongue pieces 23 and 24.
[0015]
The cut-and-raised tongue pieces 23 and 24 are formed by inserting U-shaped cut lines 232 and 242 into the flexible substrate 20. In this case, the cut-and-raised tongue pieces 23 and 24 are formed by their tongue bases. The sides (the side connected to the flexible substrate 20) face each other and are arranged symmetrically with respect to the virtual bending line XX of the bending part 21.
[0016]
According to this, by bending the flexible substrate 20 to the back side of the liquid crystal panel 10 along the virtual bending line XX, as shown in FIG. 1, each free end side of the cut and raised tongue pieces 23, 24 stands up. As a result, a substantially flat mounting surface appears at the bent portion 21, so that the chip component 30 can be mounted with high stability. Although not shown, the lead wires of the solder lands 231 and 241 may be pulled out from the base of the tongue piece.
[0017]
Next, a second embodiment of the component mounting unit 20B will be described with reference to FIG. Also in this embodiment, a pair of cut-and-raised tongue pieces 25 and 26 having solder lands 251 and 262 are provided on the component mounting portion 20B.
[0018]
In this case, the cut-and-raised tongue pieces 25, 26 are formed by inserting C-shaped cut lines 252, 262 into the flexible substrate 20, and the above-described virtual bending is performed with the tongue base portions facing each other. They are arranged side by side at predetermined intervals along the line XX.
[0019]
Also in this mode, the flexible substrate 20 is bent toward the back surface of the liquid crystal panel 10 along the virtual bending line XX, so that the cut-and-raised tongue pieces 25 and 26 are on the upper side parallel to the virtual bending line XX. And the lower side stand, a substantially flat mounting surface appears at the bent portion 21. Therefore, the chip component 30 can be mounted with high stability.
[0020]
In the first embodiment, the cut lines 232 and 242 forming the cut and raised tongue pieces 23 and 24 are substantially U-shaped. However, in some cases, the cut lines 232 and 242 are employed in the second embodiment. The cut lines 252 and 262 may be substantially C-shaped. In this sense, in the case of the present invention, the concept of a U-shape includes a C-shape.
[0021]
【The invention's effect】
As described above, according to the present invention, in the liquid crystal display element in which the flexible substrate connected to the terminal portion of the liquid crystal panel is bent by approximately 180 ° and arranged on the back side of the liquid crystal panel, By forming the component mounting portion for surface mounting the chip components, more component mounting areas can be secured on the flexible substrate.
[0022]
In addition, by providing a pair of cut-and-raised tongues formed by a substantially U-shaped cut line in the component mounting portion to make a substantially flat mounting surface appear in the component mounting portion when bending the flexible substrate, the chip Components can be mounted with high stability.
[Brief description of the drawings]
FIG. 1 is a side view schematically showing an embodiment of a liquid crystal display device according to the present invention.
FIG. 2 is an explanatory view showing a first embodiment of a component mounting unit provided in the present invention.
FIG. 3 is an explanatory view showing a second embodiment of the component mounting unit provided in the present invention.
FIG. 4 is a side view schematically showing an example of a conventional liquid crystal display element.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Liquid crystal panel 11, 12 Transparent electrode board 111 Terminal part 13 Backlight 20 Flexible board 20A, 20B Component mounting part 21 Bend part 23-26 Cut-and-raised tongue piece 231,241,251,262 Solder land 232,242,252,262 Score line 30 chip parts

Claims (3)

A liquid crystal panel having a terminal portion, and a flexible substrate having one end connected to the terminal portion, wherein the flexible substrate has a bent portion substantially 180 ° bent at a predetermined portion thereof. In a liquid crystal display element in which the other end is disposed on the non-observation surface side of the liquid crystal panel,
A liquid crystal display device, wherein a component mounting portion for surface mounting a chip component is formed in the bent portion of the flexible substrate. In the component mounting portion, a pair of cut-and-raised tongues formed by substantially U-shaped cut lines are line-symmetrical about the virtual bending line of the bent portion with their tongue bases facing each other. The liquid crystal display device according to claim 1, wherein A pair of cut-and-raised tongues formed by substantially C-shaped cut lines face the component mounting portion with their tongue bases facing each other at a predetermined interval along a virtual bending line of the bent portion. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is arranged in a manner to be arranged.

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