JPH0317628A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To increase connecting strength and to improve the reliability of connection by using wiring boards consisting of elastic members to the driving wiring part of the liquid crystal display panel and providing dummy terminals on the outer side of connecting terminals. CONSTITUTION:A video signal driving circuit is divided to upper and lower two groups which are mounted on FPC (flexible printed circuit) substrates 10a, 10c. A vertical scanning circuit is also mounted on the FPC substrate 10b. Since the driving wiring part of the liquid crystal display panel 5 is constituted of the FPCs 10a to 10c consisting of the elastic members, such as polyimide, the stresses generated in the major axis direction of the FPCs by the difference in the coefft. of expansion between the liquid crystal display panel 5 and the FPCs are absorbed by the deflection of the resilient FPCs 10a to 10c. In addition, the number of the terminals to be soldered in the junctures of the FPCs to each other is increased by providing the dummy terminals 28, the connecting strength is increased.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid crystal display device, particularly a liquid crystal display panel (LCD) provided in a window opened in a shield case, and a driving wiring section of the liquid crystal display panel. The present invention relates to a flat type liquid crystal display device built into the above-mentioned shield case, and particularly relates to a technique that is effective when applied to a liquid crystal display device that is required to be thin, have high heat resistance, and high reliability.

[Conventional technology]

For example, a conventional active matrix color liquid crystal display device in which a thin film transistor (TPT) and a pixel electrode are used as constituent elements of a pixel has a liquid crystal display panel in which a plurality of pixels are arranged in a matrix. Each pixel of the liquid crystal display panel is formed by the intersection of two adjacent scanning signal lines (also referred to as gate signal lines or horizontal signal lines) and two adjacent video signal lines (also referred to as drain signal lines or vertical signal lines). located within the area. The scanning signal lines extend in the column direction (horizontal direction) and are arranged in plural in the row direction (vertical direction). On the other hand, the video signal lines extend in the row direction intersecting the scanning signal lines, and a plurality of video signal lines are arranged in the column direction. A liquid crystal display panel includes a first substrate on which a thin film transistor, a transparent pixel electrode, a protective film for the thin film transistor, and an alignment film are sequentially provided on a first transparent glass substrate, and a color filter and a color filter on a second transparent glass substrate. a second substrate on which a protective film, a common transparent pixel electrode, and an alignment film are sequentially provided; a liquid crystal sealed between each alignment film of both substrates; and sealing of the liquid crystal provided at the periphery of the panel. It is composed of a member (sealing material). A transparent pixel electrode and a thin film transistor are provided for each pixel.

Further, one of the source electrode and drain electrode of the thin film transistor is connected to a transparent pixel electrode, the other electrode is connected to a video signal line, and the gate electrode is connected to a scanning signal line. .

A conventional liquid crystal display device, for example, mainly has two thin shield cases, upper and lower, and a thin film transistor array.
TAB is equipped with a liquid crystal display panel that is attached to a window provided in a shield case, and a semiconductor integrated circuit chip (hereinafter referred to as "Ido IC") that makes the liquid crystal display panel move.
tape automated bonding, a type of flexible printed wiring board such as polyimide), and TAB
Printed circuit board (PCB) on which chip components are mounted
rcuit B oard) ). The input terminals of the scanning signal line and video signal line provided on the outer periphery of the liquid crystal display panel and the output side outer lead of TAB (
(output terminal) are electrically connected to each other by an anisotropic conductive film (a film that allows current to flow in a direction perpendicular to its surface, but not in a horizontal direction). Furthermore, the input side outer lead (input terminal) of the TAB and the terminal of the PCB connected to a signal sending means external to the liquid crystal display device are electrically and mechanically connected by soldering. In addition, drive■
The electrode (bonding pad) of C and the inner lead of TAB are connected.

TAB equipped with a liquid crystal display panel and active IC. Each component such as a PCB is housed inside a shield case, and the two shield cases are combined and fixed by soldering. Further, each shield case is provided with a window for a liquid crystal display panel, and the liquid crystal display panel is fitted into this window so that the liquid crystal display screen can be seen through the window.

Note that a liquid crystal display device using TPT is, for example, 19
“Nikkei Electronics” 21, published September 10, 1984
It is written on the page etc. [Problems to be Solved by the Invention] In the liquid crystal display device of the prior art, four PCBs are divided and arranged on the outer periphery of the four sides of the liquid crystal display panel as idle wiring portions of the liquid crystal display panel. Since it is difficult to connect PCBs directly, each PCB was connected using a connecting FPC or the like. Therefore, since connection parts are required, the number of parts is large, and each PCB requires two connection points, resulting in a large number of connection steps and poor workability.

An object of the present invention is to provide a liquid crystal display device that can omit connecting parts and reduce the number of connecting steps.

[Means to solve the problem]

In order to solve the above problems, the liquid crystal display device of the present invention includes a shield case, a liquid crystal display panel attached to a window provided in the shield case, and a liquid crystal display panel that is electrically connected to the liquid crystal display panel. A plurality of TABs mounting related ICs that drive the liquid crystal display panel, and a plurality of TABs mentioned above.
electrically connected to the AB and equipped with the plurality of TABs mentioned above;
and a wiring board made of an elastic member, and the wiring board is divided and arranged around at least three sides of the liquid crystal display panel.

Further, the terminals of the wiring board are electrically and mechanically connected to each other.

Further, the liquid crystal display device of the present invention includes a shield case, a liquid crystal display panel attached to a window provided in the shield case, and an electrically connected to the liquid crystal display panel, and the liquid crystal display panel is moved. The circuit board includes a plurality of TABs on which tumor ICs are mounted, and a wiring board electrically connected to the plurality of TABs, on which the plurality of TABs are mounted, and made of an elastic member. TAB
It has a first terminal group for electrical connection with the wiring board and a second terminal group for connection with the outside of the wiring board, and a dummy terminal is provided outside the second terminal group. shall be.

[Effect]

In the liquid crystal display device of the present invention, since the wiring board made of an elastic material is used as the drive wiring part of the liquid crystal display panel, each wiring board can be directly connected, so connecting parts can be omitted and the number of connection steps can be reduced. can. Further, by providing a dummy terminal outside the connection terminal, the connection strength can be increased and the reliability of the connection can be improved.

Other objects and features of the invention will become apparent from the following description with reference to the drawings.

〔Example〕

Fig. 2 is a plan view of a main part of one pixel of the liquid crystal display section of an active matrix color liquid crystal display device to which the present invention is applied, and Fig. 3 is a plan view taken along the section line 11-■ in Fig. 2. 4 is a plan view of the main part of the liquid crystal display section in which a plurality of pixels shown in Fig. 2 are arranged, and Fig. 5 is a plan view of the main part depicting only the pixel electrode and color filter layer shown in Fig. 4. 6 are equivalent circuit diagrams of the liquid crystal display section.

<Pixel Arrangement> As shown in Figure 2, each pixel is connected to two adjacent scanning signal lines (gate signal lines or horizontal signal lines) OL and two adjacent video signal lines (train signal lines or vertical signal lines). (signal line) DL (in the area surrounded by the four signal lines). As shown in FIGS. 2 and 4, the scanning signal lines GL extend in the column direction (horizontal direction) and are arranged in plural in the row direction (vertical direction). The video signals I DL extend in the row direction, and a plurality of video signals I DL are arranged in the column direction.

<<Overall Structure of Panel Cross Section>> As shown in FIG. 3, the liquid crystal display panel includes a thin film 1, a transistor TFT1, and a transparent pixel electrode TO. l, a first substrate on which a protective film psv1 of the thin film transistor TPT and a lower alignment film ORI for setting the orientation of liquid crystal molecules are sequentially provided; a black matrix BM, a color filter FIL, and a color filter FIL on an upper transparent glass substrate SUBZ;
A second substrate on which a protective film PSV2, a common transparent pixel electrode IT○2, and an upper alignment film ORI2 are sequentially provided, and both substrates S
It is composed of a liquid crystal LC sealed between each of the alignment films ORTL and ORI2 of UBI and SUB2, and a sealing material SL provided around both substrates to seal the liquid crystal LC between both substrates.

The thickness of the lower transparent glass substrate SUBI is, for example, 1.
]. It is about on.

The center part of Figure 3 shows the cross section of the monomer element part, while the left side shows the cross section of the left edge part of the transparent glass substrates SUBI and SUB2 where the external lead wiring is present. On the right side, transparent glass substrates SUBI and SUB
2 shows a cross-section of the right side edge of FIG. 2 where no external lead wiring is present.

In the method for manufacturing a liquid crystal display panel, the first substrate and the second substrate are formed separately so that the alignment films ORII and ORI2 of both substrates face each other. Both substrates are stacked at a predetermined distance by interposing a spacer material (not shown) between them, liquid crystal LC is sealed between both substrates, and sealed with a sealing material SL provided around both substrates. It is assembled by A backlight BL is arranged on the lower transparent glass substrate SUBI side.

The sealing materials SL shown on the left and right sides of FIG. 3 are as follows:
It is configured to seal the liquid crystal LC, is provided along the entire edge of the transparent glass substrates SUBI and SUB2 except for the liquid crystal sealing opening (not shown), and is made of, for example, epoxy resin. .

Common transparent electrode ITO2 on the upper transparent glass substrate SUBZ side
is connected to an external lead wiring provided on the lower transparent glass substrate SUB1 side at least in one place by a silver paste material SIL. This external lead wiring is formed of a transparent pixel electrode layer IT○l.

Orientation films ORII and ORI2, transparent pixel electrode ITOI
, the common transparent electrode ITO2 is provided inside the sealing material SL. The polarizing plate POL has a lower transparent glass substrate SUBI
, are provided on the outer surface of each of the upper transparent glass substrates SUB2.

Transparent pixel electrode IT○1 and thin film transistor TPT are:
It is provided for each pixel.

<Thin film transistor TPT> The thin film transistor TPT of each pixel has three
It is divided into two (plurality) of thin film transistors (divided thin film transistors) TFTI, TPT2, and TFT3. Each of the thin film transistors TFTI to TFT3 has substantially the same dimensions (channel length and width are the same). Each of the divided thin film transistors TPT1 to TFT3 mainly has a gate electrode GT.
, gate insulating film GI, i-type (intrinsic)
i-type semiconductors/IAs. It consists of a pair of source electrode SDI and drain electrode SD2. Note that the source and drain are originally determined by the bias polarity between them, and in the circuit of a liquid crystal display device, the polarity is reversed during operation, so it should be understood that the source and drain are interchanged during operation. However, even in the explanation below,
For convenience, one is expressed as a source and the other as a drain.

The source electrode isD1 of the thin film transistor TPT is connected to the transparent pixel electrode ITOI, the drain@pole SD2 is connected to the video signal line DL, and the gate electrode GT is connected to the scanning signal line GL.

<<Light-shielding film BM>> In order to shield the thin-film transistors TPT1 to TPT3 from the upper transparent glass substrate SUB2 side, the scanning signal line GL, video signal line DL, and thin-film transistor TP of the substrate SUB2 are used.
A black matrix BM made of a chromium layer or the like is provided in a portion corresponding to T. As a result, the outline of each pixel becomes clear due to the light shielding film BM, and the contrast is improved. In other words, the light shielding film BM has two functions: shielding the semiconductor layer AS from light and serving as a black matrix.

In addition, the backlight is installed on the SUBZ side, and the SUBI
can also be set to the I1 side (externally exposed side).

<Common electrode ITO2> The common transparent electrode IT○2 is connected to the lower transparent glass substrate SUBI
It is arranged to face the transparent pixel electrode ITOI provided for each pixel on the side, and is configured to be common to a plurality of pixel electrodes To.

A common voltage is applied to this common transparent electrode ITO2. 6 <Color Filter FIL> The color filter FIL is a color filter that colors a dye base material made of a resin material such as acrylic resin. It is composed of
As shown in FIG. 5, the color filter FIL is shaped like a dot for each pixel at a position facing the pixel, and is colored differently (FIG. 5 shows the third conductive film layer d3 in FIG. 4). This is a drawing of only the color filter layer FIL, and each of the red R, green G, and blue B filters is hatched with a 45'.135° cross.)

<<Pixel Arrangement>> As shown in FIGS. 4 and 5, a plurality of pixels of the liquid crystal display section are arranged in the same column direction as the direction in which the scanning signal line GL extends, and are arranged in pixel columns X1, X2, X3. ,X4. ...
It consists of each of the following. Each pixel column X1, X2, X3
, X4, . . . have thin film transistors TFTI to TFT3 and transparent pixel electrodes El to E3 arranged in the same position. In other words, odd pixel column X1
, X3,... each pixel is a thin film transistor T
PT] ~ Place TFT3 on the left side. Transparent pixel electrode E
1 to E3 are arranged on the right side. Each pixel in the even numbered pixel columns X2, X4, . . . adjacent to each of the odd numbered pixel columns X1, X3, . . . . each pixel is made up of pixels that are symmetrically turned upside down with respect to the extending direction of the video signal line DL. That is, pixel columns X2, X4,
Each pixel of... is a thin film transistor TPT]
．． ~T F T3 is placed on the right side, transparent pixel electrode E1
-E3 are arranged on the left side. Then, pixel columns x2, X4 . Each pixel in pixel rows X1 and X3
, . . . are shifted (shifted) by half a pixel interval in the column direction. In other words, if each pixel interval of pixel row X is 1.0 (1.0 pitch),
The next pixel column X has a pixel interval of 1.0, and is shifted from the previous pixel column X by 0.5 pixel intervals (0.5 pinochs) in the column direction. The video signal line DL1 extending in the row direction between each pixel is a half pixel interval (0.
5 pitches) in the row direction.

As a result, as shown in FIG. 5, the pixels in the previous pixel row The pixels on which the same color filter is formed (for example, the pixel on which the red filter R of pixel row X4 is formed) are separated by 1.5 pixel intervals (1.5 pitch), and the RGB color filter FIL is It will be a triangular arrangement. Color filter FI
The triangular arrangement structure of RGB of L can improve the color mixing of each color, and therefore can improve the resolution of a color image.

Further, since the video signal line DL extends in the column direction by only half a pixel interval in each pixel column XlfiJ, it does not intersect with the adjacent video signal line 1)L. therefore,
It is possible to eliminate the routing of the video signal lines DL and reduce the area occupied by the video signal lines DL, and it is also possible to eliminate the detours of the video signal lines D2 and to eliminate the multilayer wiring structure.

《Whole display panel equivalent circuit》 FIG. 6 shows an equivalent circuit of this liquid crystal display device.

jG. Xi+IG, . . . are video signal lines (horizontal signal lines) D L connected to the pixels in which the green filter G is formed.
It is. XiB. Xi+IB. ... is a video signal 9-line DL connected to the pixel in which the blue filter B is formed. Xi+IR. Xi+2R,... is the red filter R
A video signal line DL is connected to a pixel in which a pixel is formed.

These video signal lines DL are operated by video signal dynamic circuits (horizontal gap circuits) provided above and below the liquid crystal display panel. Yi is a scanning signal line (vertical signal m) ar= which selects the pixel column X1 shown in FIGS. 4 and 5. Similarly, Yi+1, Yi+2. Each of ... is a pixel column
2, X3, . . . scanning signal line GL that selects each of
It is. These scanning signal lines OL are connected to a vertical scanning circuit (vertical 'RM?JJ circuit) provided on the left side of the two liquid crystal display panels. To the right of the liquid product display panel is the power supply circuit PS and the CRT from the host (upper processing unit).
A circuit cN■ for converting information for a cathode ray tube (cathode ray tube) into information for a TPT liquid crystal display panel is provided, and these circuits are connected to a PC (described later).
It will be installed on B11. The video signal bow (horizontal) opening circuit is divided into two groups below.FPC (flexible)
The vertical scanning (vertical scrapping) circuit is also mounted on the FPC board 1.
It is installed in 0b.

In order to ensure a sufficiently large connection terminal pitch, the horizontal signal lines DL are alternately connected to the upper and lower FPCJJ boards 10a, 1. Oc
connected to. The power supply circuit Ps receives DC potentials of Ov, 5V and 25V from the outside, and creates new DC potential sources of 13V and 21V. In the vertical scanning circuit base 10b,
From the power supply circuit Ps, 0■, 5■, and 25V DC current (,2) are supplied via the wiring formed on the FPC board 10a, and the scanning line Yi receives binary dynamic pulses of OV and 25V. Applied.Video signal floating circuit board 1oa.loc
are supplied with DC potentials of OV, 5V, 13V, and 21V from the power supply circuit ps, and the signal aXi is supplied with DC potentials of 5V, 13V, and 2V.
A 1V tri-level annotation pulse is applied. Note that this heel movement example uses a VDT (Video Display Terminal) with 8-gradation color display.
This is the case for nal) ).

The vertical scanning circuit board 10b is connected to the horizontal scanning IH and one vertical scanning 1V from the CRT-+TFT conversion circuit CNV via the wiring formed on the lower horizontal scanning circuit board 10C.
Two synchronization pulses corresponding to .

1(A) to 1(J) are diagrams showing an embodiment of the liquid crystal display device of the present invention, respectively. FIG. 1(A) is a plan view showing the internal structure of the liquid crystal display device, and FIG. B), (C), (D
) are a plan view, a front view, and a side view showing the external appearance of the liquid crystal display device, FIG. ), (G), and (H) are the plan views of each FPC, respectively.
Figure 1 (I) is a cross-sectional view of FPC, Figure 1 (J) is FPC
FIG.

The liquid crystal display device of the present invention will be explained based on each episode. The external appearance of the liquid crystal display device of this embodiment is shown in the plan view, front view, and side view of FIGS. 1(B) to 1(D). The liquid crystal display device of this embodiment is covered with two thin rectangular upper and lower shield cases 1 and 2 made of metal, for example, which are combined and fixed by soldering or the like.

Liquid crystal display windows 3 and 4 provided in shield cases l and 2 (
A liquid crystal display panel 5 is attached to the display panel 4 (not shown here). Inside the shield cases 1 and 2 are heel motion ICs. T
AB. FPC. Active wiring circuit such as PCB, power supply circuit PS
and peripheral circuits CNV, etc. are built-in. 6 is a connector portion into which a connector for sending data from a personal computer or the like is inserted.

The internal structure of the liquid crystal display device of this example is shown by the plan view of Fig. 1 (A). 7 is a moving IC for operating the liquid crystal display panel 5, 8 is a passive element chip component such as a capacitor or a resistor, and 9 is a TA on which the moving IC 7 is mounted.
B, 10a. 10b and ↓Oc are FPCs (flexible printed circuit boards) made of elastic material such as polyimide, and on which TAB9 and chip components 8 are connected and mounted.
PC10a and 10c are video signal side (horizontal signal side) Fpc
, 10b is a scanning signal side (vertical signal side) FPC. 1
Reference numeral 1 indicates a PCB made of glass epoxy or the like, which is equipped with a conversion circuit CNV and a power supply circuit PS for converting CRT data sent from a personal computer or the like via the connector section 6 into data for a TPT liquid crystal display device; LCD display panel 5
The input terminals of the liquid crystal display panel 5 are provided on the outer periphery of the three sides, and 13 is the output terminal of the TAB 9 (output side outer lead).
, 14 is the input terminal of TAB9 (input side outer lead),
15 is an output terminal of the FPCs 10a to 10c.

Reference numeral 25 denotes a plurality of reinforcing plates provided at the connection part of the TAB 9 (location of the output terminal 15 of the FPC) and the mounting part of the chip component 8 in the FPCs 10a to lOc, and the reinforcing plates 25 are divided in the longitudinal direction of the FPC. A gap is provided between each reinforcing plate 25. 26 is each F P
Each FPC at the connection part of C10a to 10c comrades
are provided at both ends.

The liquid crystal display panel 5 is fitted and fixed into the liquid crystal display window of the lower shield case 2. A plurality of TAB9s equipped with the ICs 7 are arranged around the outer periphery of the three sides of the liquid crystal display panel 5, and are connected to the liquid crystal display panel 5 and the FPCs 10a to 10a.
It is electrically connected to 10c. FPC10a~10
c are attached to the lower shield case 2, respectively. For example, small holes 16 are drilled through the FPC10a to 10c and the reinforcing plate 25 at several predetermined locations, and these holes 16 are fitted into pins 17 that are integrally provided on the lower shield case 2. By FPC10a~1
0c is fixed to the lower shield case 2.

A PCB 11 is mounted on the outer periphery of the remaining side of the liquid crystal display panel 5, and is equipped with a power supply circuit and a conversion circuit for converting data for a CRT into data for a TPT liquid crystal display device. The FPCs 10a and 10c located at the top and bottom of the figure are provided with a video signal fluctuation circuit, and the FPC 10 located at the left
A vertical scanning circuit is provided in b, and the PC located on the right
B. L1 is provided with a power supply circuit ps and a CRT-+TPT conversion circuit CNV (see the equivalent circuit diagram in Fig. 6. The equivalent circuit diagram in Fig. 6 is drawn corresponding to Fig. 1 (A)). ). In addition, please note that there is no FPC on the outer periphery of the work area.
1 was used because there is no problem of lead wire breakage as with three-sided FPCs, and there are many components to be soldered here, such as power supply circuits and conversion circuits. but. FPC and reinforcing board may be used instead of PCB.

Since TAB9 and chip capacitor 8 are thin,
FPC board 1. 0a to 10c, but the power supply circuit PS and conversion circuit CNV are not chip-shaped, but are sealed with plastic or ceramic, and may be made of integrated circuits (ICs), transistors, passive components, etc. that have external leads. Because of the thickness, the PCB l
1, and the display surface (top surface) is designed to be as flat as possible.

The chip capacitor 8 is a bypass capacitor for ripple removal electrically connected to the DC potential wiring from the power supply circuit PS mentioned above, and in order to increase mounting efficiency,
FIG. 1(E) shows the electrical connections between the liquid crystal display panel 5 and the TAB 9, and the electrical connections between the TAB 9 and the housing I.
Electrical connection with C7, TAB9 and FPC10
Electrical connections with a to 10c are shown.

The liquid crystal display panel 5 has a lower transparent glass substrate SUBI. It is composed of an upper transparent glass substrate SUB2, and a liquid crystal LC is sealed between both transparent glass substrates and sealed with a sealing material SL. 4 is a liquid crystal display window provided in the lower shield case 2. 12 is an input terminal of the liquid crystal display panel 5 provided on the outer periphery of the liquid crystal display panel 5 (the edge of the lower glass substrate SUBI); 1-
3 is the output side outer lead of 'rAB9, 18 is the opening IC
7 electrode, 19 is TAB9 inner lead, 14 is TA
B3 input side outer lead. 15 is FPC10a~10
This is the output terminal of c. Note that the input terminal 12 of the liquid crystal display panel 5 extends in the column direction as described above, and is connected to the ends of the scanning signals k@GL, which are arranged in plurality in the row direction. This is the end of a plurality of video signal lines DL extending in the row direction and arranged in the column direction.

The input terminal 12 of the liquid crystal display panel 5 and the output side outer lead l3 of the TAB 9 are connected by an anisotropic conductive film 20.

Inner lead 19 of TAB9 and electrode 18 of groove rC7
are connected.

TAB9 input side outer lead 14 and FPC]. O
The output terminals 15 of a to ↓Oc are electrically and mechanically connected by soldering.

Figure 1 (F), (G). Plan view of (H) and Figure 1 (I)
According to the cross-sectional view of each FPC1. O a ~1 0
c is shown. Fig. 1(F) is a plan view showing the signal side FPC 10a, and Fig. 1(G) is a plan view of the scanning side FPC I.
A plan view showing Ob, Figure 1 (H) is the signal side FPC10c
FIG.

In this embodiment, F, which is the sleep wiring section of the liquid crystal display panel S,
The PC is shown in Figure 1 (F). As shown in (G) and (}l), three FPCs 10a, fob.
10c. Each FPC 1. Oa
-10c is provided with an input terminal (not shown) and an output terminal 5, and also has a chip component 8 mounted thereon.

(F). The terminal shown by the broken line in (H) indicates that the terminal surface is on the back side. In addition, each FPC is provided with a hole 16, and a pin 17 (see FIG. 1 (A)) provided integrally with the lower shield case 2 is inserted into the hole 16 to allow the FP to open.
C is held in the lower shield case 2. Reference numeral 26 denotes a connecting portion for connecting FPCs, which will be described in detail later.

FIG. 1(I) is a cross-sectional view of the FPC. 2] is a base film made of polyimide or the like with a layer thickness of, for example, 25 μm;
22 is a cover film made of polyimide or the like with a layer thickness of 25 μm; 23 is a conductor made of rolled copper foil with a layer thickness of 35 μm; 2
4 is a thermosetting adhesive layer having a layer thickness of 20 to 25 μm.

In this way, the FPC is constructed from three polyimide layers, and the connection parts 26 (Fig. 1 (F) to (H)) between the FPCs are
The base film 21 is composed of one polyimide layer, that is, a base film 21.

Figure 1 (J) shows FPCIOa~10 divided into three parts.
c is an enlarged partial plan view showing a connecting part 26 having terminals for connecting two parts. Reference numeral 26 indicates a connecting portion between the FPCs 10a to 10c; 27 indicates a terminal for connecting the FPCs 10a=10c; and 28 indicates a plurality of dummy terminals provided on both sides of the terminal 27.

The dummy terminal 28 is not normally used. In other words, it is a terminal from which the display circuit is electrically disconnected, and is electrically floating. The connecting portion 26 is composed of only one layer, that is, the base film 21 shown in FIG. 1(I), and is flexible.

In the liquid crystal display device of this embodiment, the floating wiring portion of the liquid crystal display panel 5 is made of an FPC 10a made of an elastic material such as polyimide.
~10c, so the LCD panel 5 and F
The stress generated in the long axis direction of the FPC due to the difference in expansion rate of the PC is absorbed by the bending of the flexible PFCs 10a to 10c, preventing the input side outer lead 14, which has the weakest strength of the TAB 9, from being cut. Therefore, the reliability of the liquid crystal display device against heat can be improved. In addition, as liquid crystal display screens become larger, the larger the size of the liquid crystal display device, the heavier the wiring section including the TAB becomes. FPCs are lighter than conventional PCBs, so the power wiring can be made lighter. The load on the input-side outer lead 14 of the TAB 9 can be reduced, and reliability against vibrations and shocks can be improved.

Furthermore, the weight of the entire liquid crystal display device can be reduced.

Also, TAB of FPC 10a to 10c
A reinforcing plate 25 is provided at the connection part 9 and the mounting part of the chip component 8, reinforcing the FPC from the back. TAB9
The connection and the mounting of the chip components 8 can be performed stably and easily, resulting in good workability. In addition, the reinforcing plate 25 is FPC10
Since it is divided in the long axis direction of a to 10c, flexible F
P C 1 0 a = 1 0 The stress is effectively absorbed by the deflection of P C 1 0 a = 1 0 c.

Furthermore, as shown in FIG. 1 (J), a connecting FPC for connecting divided PCBs as in the prior art is used.
, and other connecting parts can be omitted, and the number of connecting steps can be reduced by half. Further, since the connecting portion 26 is composed of only one layer and is highly flexible, it is easy to connect the FPCIOs a to 10c and can absorb stress. In addition, the dummy terminal 28
By providing this, it is possible to increase the number of terminals to be soldered at the joints between FPCs, thereby increasing the connection strength. In this way, this embodiment can improve the reliability of the connection between the two. Note that connecting the dummy terminal 28 to a DC power supply wiring (AC grounding point) such as a ground wiring is effective as a countermeasure against noise.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and it goes without saying that various changes can be made without departing from the spirit of the invention.

〔Effect of the invention〕

As explained above, according to the liquid crystal display device of the present invention,
Since the wiring board made of an elastic member is used as the dynamic wiring part of the liquid crystal display panel, each wiring board can be directly connected, the number of connecting parts can be saved, and the number of connection steps can be reduced. In addition, a dummy terminal was provided outside the connection terminal, so
Connection strength can be increased and connection reliability can be improved.

[Brief explanation of the drawing]

FIG. 1(A) is a plan view showing the internal structure of an embodiment of the liquid crystal display device of the present invention, and FIG. 1(B) is a plan view showing the external appearance of the liquid crystal display device of the present embodiment. Figure (C) is a front view of Figure 1 (B), Figure (D) is a side view of Figure 1 (B), and Figure 1 (E) is a liquid crystal display panel/TAB-heel movement. I
Diagram showing each connection state of C-FPC, Figure 1 (F), CG
), (H) are the plan views of each FPC, and Figure 1 (I) is the FPC.
FIG. 1 (J) is a cross-sectional view of the PC, and FIG. 1 (J) is a plan view showing the connection part of the FPC. FIG. 3 is a cross-sectional view taken along the line nn in FIG. 2, FIG. 4 is a plan view of a main part of a liquid crystal display section in which a plurality of pixels shown in FIG. 2 are arranged, and FIG. 5 is a plan view. is a plan view of the main part depicting only the pixel electrode and color filter layer shown in FIG. 4, and FIG.
FIG. 3 is an equivalent circuit diagram of the liquid crystal display section of this embodiment. 1... Upper shield case 2... Lower shield case 3... Upper shield case liquid crystal display window 4... Lower shield case liquid crystal display window 5... Liquid crystal display panel ps... Power supply circuit CNV.・・CRT-+TFT conversion circuit 6 ・・Connector part 7 ・Opening IC 8 ・Chip parts 9 ・TAB 10a, 10b, ↓O c - F P C1l...
PCB 12...Input terminal 13 of liquid crystal display panel...Output side outer lead of TAB 14...Input side outer lead of TAB 15...FP
C output terminal 16...hole 17...pin SUBI...lower transparent glass substrate SUB2...upper transparent glass substrate LC...liquid crystal SL...sealing material 18...opening IC electrode 19 ... TAB inner lead 20 ... anisotropic conductive film 21 ... base film 22 ... cover film 23 ... conductor 24 ... adhesive layer 25 ... reinforcing plate 26 ... FPC connection part 27...FPC terminal 28...Dummy terminal

Claims (1)

[Claims] 1. A shield case, a liquid crystal display panel attached to a window provided in the shield case, and a drive IC that is electrically connected to the liquid crystal display panel and drives the liquid crystal display panel. a plurality of TABs to be mounted; a wiring board electrically connected to the plurality of TABs, on which the plurality of TABs are mounted, and made of an elastic member; A liquid crystal display device characterized in that it is divided and arranged around three sides. 2. The liquid crystal display device according to claim 1, wherein the terminals of the wiring board are electrically and mechanically connected to each other. 3. A shield case, a liquid crystal display panel attached to a window provided in the shield case, and a plurality of TABs electrically connected to the liquid crystal display panel and mounting drive ICs for driving the liquid crystal display panel. , a wiring board electrically connected to the plurality of TABs, mounted with the plurality of TABs, and made of an elastic member, the wiring board having a first wiring board for electrical connection with the plurality of TABs. A liquid crystal display device comprising a terminal group and a second terminal group for connection with the outside of the wiring board, and a dummy terminal is provided outside the second terminal group.