JPH0317627A - display device - Google Patents

Abstract

PURPOSE:To relieve the stress occurring in the difference in coefft. of expansion between a liquid crystal display panel and driving wiring part and to prevent the disconnect of leads at the time of automatic bonding of tapes by using an elastic member to constitute the driving wiring part of the liquid crystal display panel. 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 member, 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 resislient FPCs 10a to 10c. The cutting of an input side outer lead 14 which is weakest in strength of a TAB 9 is, therefore, prevented and the reliability of the liquid crystal display device on heat is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a display device, in particular, a liquid crystal display panel (LCD) is provided in a window opened in a shield case, and the driving wiring portion of the liquid crystal display panel is connected to the It relates to flat type liquid crystal display devices built into shield cases, especially thin,
The present invention also relates to a technique that is effective when applied to liquid crystal display devices that require 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 multiple lines 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 are arranged in plural in the column direction.

A liquid crystal display panel includes thin film transistors and transparent pixel electrodes on a first transparent glass substrate. - A second substrate on which a transistor protective film and an alignment film are sequentially provided, and a second transparent glass substrate on which a color filter, a color filter protective film, a common transparent pixel electrode, and an alignment film are sequentially provided.
a substrate, a liquid crystal sealed between each alignment film of both substrates,
This is achieved by a sealing member (sealing material) for the liquid crystal provided around the periphery of the panel. 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.
A TAB 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 a drive IC) that disturbs the liquid crystal display panel.
(a type of flexible printed wiring board such as tape automated bonding and polyimide) and TA
Printed wiring board (PCB:
Prinide circuit board
dC circuit board)). 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 (output terminal) of the TAB are connected to an anisotropic conductive film (current flows in the direction perpendicular to the surface). However, they are electrically connected by a membrane that does not flow horizontally. Also, T
The input side outer lead (input terminal) of AB 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. Furthermore, the electrodes (bonding pads) of the commotion IC and the inner leads of the TAB are connected.

Each component, such as the liquid crystal display panel, the TAB with the commotion IC mounted, and the PCB, is built into the shield case, and the two shield cases are combined and fixed by soldering. Furthermore, each shield case is provided with a window for the 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 the liquid crystal display device using TPT is, for example, 198
“Nikkei Electronics J 21” published on September 4th, IO
It is written on the page etc.

[Problem to be solved by the invention]

In the conventional technology, no consideration is given to the occurrence of stress due to the difference in expansion coefficient between the liquid crystal display panel made of a glass member and the PCB which is the drive wiring part of the panel.
Stress wrinkles appear on TAB, and T is the weakest in strength.
AB input side outer lead (code 14 in Figure 1 (E))
There is a problem with the connection being disconnected. In addition, as liquid crystal display screens become larger, the larger the dimensions of the liquid crystal display device, the heavier the wiring section including the TAB becomes.
The load on the input-side outer lead of the device also becomes heavier.

An object of the present invention is to provide a liquid crystal display device that can prevent disconnection of the input side outer lead of the TAB.

[Means to solve the problem]

In order to solve the above problems, the display device of the present invention includes a liquid crystal display panel, a TAB that is electrically connected to the liquid crystal display panel and includes a drive IC that causes the liquid crystal display panel to operate late, and electrically connected to the above TA
A wiring board on which B is mounted, and the wiring board is made of an elastic member.

Further, the display measure of the present invention (1) extends in the horizontal direction;
A plurality of vertical signal lines are arranged in the vertical direction, and the lines extend in the vertical direction. A plurality of horizontal signal lines arranged in the horizontal direction, opposing first and third sides, and opposing second and fourth sides.
(2) first and second horizontal drive circuits for driving the horizontal signal lines arranged on the second and fourth sides; (3) the third horizontal drive circuit; (4) a vertical drive circuit arranged on the first side for driving the vertical signal line; It is characterized by comprising an interface circuit for operation.

Further, the above-mentioned interface circuit is connected to the above-mentioned t-th and second
and a power supply circuit for the horizontal drive circuit and the vertical adjustment circuit, and a circuit for converting an external cathode ray tube display signal into an active matrix liquid crystal display signal. Each of the first and second horizontal drive circuits and the vertical drive circuit is attached to a wiring board made of a first material, and the interface circuit is attached to a first, second and third wiring board portion made of a second material. The first material is characterized in that it has greater elasticity than the second material.

Furthermore, the wiring from the interface circuit to the vertical display circuit is arranged so as to be connected to the third wiring board part via the first and second wiring board parts.

Furthermore, a capacitor is disposed at both ends of each of the first and second horizontal drive circuits.

[Effect]

In the display device of the present invention, since the dynamic wiring portion of the liquid crystal display panel is constructed from an elastic member and a certain wiring board, the stress in the long direction caused by the difference in expansion coefficient between the liquid crystal display panel and the dynamic wiring portion is reduced. This is absorbed by the bending of the flexible wiring board, and can prevent the input side outer lead of the TAB from being cut. Furthermore, since the flexible wiring board is light, the drive wiring section including the TAB can be made lighter, and the load on the input-side outer lead of the TAB can be reduced.

The display matrix includes a vertical signal line, a horizontal signal line, and four sides, and first and second horizontal fluctuation circuits. By arranging the vertical gloss circuit and the interface circuit as described above, a compact and highly reliable display device can be provided.

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 an essential part of one element of the liquid crystal display part 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 cutting line 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 main part showing only the pixel electrode and color filter layer shown in Fig. 4. The plan view, Figure 6, is
FIG. 3 is an equivalent circuit diagram of a 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) GL and two adjacent video signal lines (drain signal lines or vertical signal lines). Signal I
IA) It is located within the intersection area with DL (within the area surrounded by four signal lines). As shown in FIGS. 2 and 4, the scanning signal lines OL extend in the column direction (horizontal direction) and are arranged in plural in the row direction (vertical direction). The video signals mDL extend in the row direction, and a plurality of video signals mDL are arranged in the column direction.

《Overall cross-sectional structure of the panel》 As shown in Fig. 3, the liquid crystal display panel includes a thin film transistor TFTI, a transparent pixel electrode IT○1, a thin film transistor TFT protection 1lgpsv1, and a liquid crystal molecule on a lower transparent glass substrate SUBI with the liquid crystal layer LC as a reference. A black matrix BM, a color filter FIL, and a color filter FIL are provided on a first substrate on which an orientation film ORE1 is sequentially provided, and an upper transparent glass substrate SUB2.
A second substrate on which a protective film PSV2, a common transparent pixel electrode ITO2, 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 ○RII and ○RI2 of UBI and SUB2, and a sealing material SL provided around both substrates to seal the liquid crystal LC between both substrates. There is.

The thickness of the lower transparent glass substrate SUBI is, for example, 1.1n.
It is about n.

The center part of FIG. 3 shows a cross section of one pixel, while the left side shows a cross section of the left edge part of the transparent glass substrates SUBI and StJB2 where external lead wiring is present. The right side shows a cross section of the right edge portion of the transparent glass substrates SUBI and SUB2 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, and a spacer material is provided between the two substrates so that the alignment films ○RII and ○RI2 of both substrates face each other. (not shown), the two substrates are stacked at a predetermined distance, the liquid crystal LC is sealed between the two substrates, and the two substrates are sealed with a sealing material SL provided around the periphery of the two substrates. 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 periphery 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 SUBl side at least in one place by a silver paste material SIL. This external lead wiring is formed of the transparent pixel electrode layer ITO1.

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.

What is the transparent pixel electrode ITOI and the thin film transistor TPT?
It is provided for each pixel.

<Thin film transistor TPT> The thin film transistor TPT of each pixel has three
The thin film transistor (divided thin film transistor) TFTI. It is composed of TFT2 and TFT3. Each of the thin film transistors TPTI 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 G-
T, gate insulating film GI, i type (intrinsi)
c, an i-type semiconductor RAS made of a non-quality silicon (Si) semiconductor (not doped with conductivity type determining impurities), and a pair of source electrodes SDI and drain electrodes 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 following explanation,
For convenience, one is expressed as a source and the other as a drain.

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

<<Light-shielding film BM>> In order to shield the thin-film transistors TPTI-3 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 J'lAS and serving as a black matrix.

In addition, attach the backlight to the SUB2 side, and
can also be set as the observation side (externally exposed side).

<<Common electrode ITO2)) The common transparent electrode ITO2 is connected to the lower transparent glass substrate SUBI
It is arranged opposite to 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 IT○2.

<Color Filter FIL> The color filter FIL is constructed by applying a dye to a dyed base material made of a resin material such as acrylic resin.
As shown in FIG. 5, the color filter FIL is formed into a dot shape for each pixel at a position facing the pixel, and is colored differently (FIG. 5 shows the third conductive film N( 13
It depicts only the color filters IFIL, red R,
The green G and blue B filters are 45° and ■35°, respectively.
゜Cross hatched).

<<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,...
・Constitutes each of the following. Each pixel column X1, X2, X
3. In each of the pixels X4, . . . , the thin film transistors TPTI to TFT3 and the transparent pixel electrodes E1 to E3 are arranged in the same position. In other words, odd pixel row
In each of the pixels No. 1, X3, . . . , the thin film transistors TPTI to TFT3 are arranged on the left side, and the transparent pixel electrodes E1 to E3 are arranged on the right side. Odd pixel row Xi. Each pixel in the even-numbered pixel columns X2, X4, . . . adjacent to each other in the row direction of X3, . . . It is made up of pixels that are symmetrical and upside down with respect to the extending direction. That is, pixel columns X2, X4
,... each pixel is a thin film transistor TFT.
The placement position of I-TFT3 is on the right side, transparent pixel electrodes E1 to E
3 is located on the left side. And pixel row X
Each pixel of 2, X4, ... is a pixel column X1, X
3, . . . are shifted (shifted) by half a pixel interval in the column direction. In other words, if each pixel interval of both pixel columns X is 1.0 (1.0 pitch), then the next pixel column 0.5 pixel interval (0
．． 5 pitches) is off. The video signal line DL extends between each pixel in the row direction. Between each pixel row X, it is configured to extend in the row direction by half a pixel interval (0.5 pitch).

As a result, as shown in FIG. The pixels on which color filters are formed (for example, the pixels on which the red filter R of pixel row becomes. Color filter FIL
The triangular arrangement structure of RGB can improve the mixing of each color, thereby improving the resolution of a color image.

Further, since the video signal mDL extends in the column direction by only half a pixel interval between each pixel column X, it does not intersect with the adjacent video signal line DL. Therefore, video signal 4Q
It is possible to eliminate the routing of the DL and reduce its occupied area, and it is also possible to eliminate the detour of the video signal line DL and eliminate the multilayer wiring structure.

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

iG. Xi+IG, . . . are video signal lines (horizontal signal lines) DL connected to pixels on which the green filter G is applied. XiB, Xi+IB,... is blue filter B
is the video signal line DL connected to the pixel to be shaped.
Xi+IR. Xi+2R, . . . are video signals gDL connected to the pixels in which the red filter R is formed. These video signals IDL are driven by video signal drive circuits (horizontal drive circuits) provided above and below the liquid crystal display panel. Yi is a scanning signal line (vertical signal line) OL that selects the pixel column X1 shown in FIGS. 4 and 5. Similarly, Yi
+1, Yi+2, . . . are pixel columns X2, X
This is a scanning signal line GL that selects each of 3, . These scanning signals MGL are connected to a vertical scanning circuit (vertical motion circuit) provided on the left side of the liquid crystal display panel. To the right of the liquid crystal display panel is the power supply circuit PS and the host (
A circuit CN that converts information for a CRT (cathode ray tube) from a higher-level processing unit into information for a TPT liquid crystal display panel.
V are provided, and they are mounted on PCB 1 1, which will be described later. The video signal (horizontal) active circuit is divided into two groups, upper and lower, and mounted on FPC (flexible printed circuit) boards 10a and 10c, and the vertical scanning (vertical active) circuit is similarly mounted on the FPC board 10b. ing.

The horizontal signal lines DL are alternately connected to the upper and lower FPC boards 10a and 10c in order to ensure a sufficiently large connection terminal pitch. The power supply circuit PS is externally connected to OV. 5V and 25V
new DC potential sources of 13V and 21V are created. The vertical scanning circuit board 10b includes a power supply circuit P.
Direct current potentials of OV, 5V and 25V are supplied from S via wiring formed on the FPC board 10a, and binary drive pulses of Ov and 25V are applied to the scanning node Yi. The video signal switching circuit board 10a, loc is connected to the power supply circuit ps to OV. DC potentials of 5V, 13V, and 2LV are supplied, and three-value drive pulses of 5V, 13V, and 21V are applied to the signal line Xi. This drive example uses a VDT (Video Display Terminal) with 8-gradation color display.
This is the case for deoDisplay Tara+inal)).

The vertical drive circuit board 10b receives one horizontal scan 1H and one vertical scan 1V from the CRT-+TPT conversion circuit CNV via wiring formed on the lower horizontal drive 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.
F), (G), and (H) are respectively plan views of each FPC, FIG. 1 (I) is a cross-sectional view of the FPC, and FIG. 1 (J) is a plan view showing the connecting portion of the FPC.

The liquid crystal display device of the present invention will be explained based on each figure.

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. 1CB) to 1D. 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 1 and 2 (
A liquid crystal display panel 5 is attached to the display panel 4 (not shown here). Inside the shield case L 2 is an inductive IC, T.
AB. FPC. Dynamic 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 plan view of FIG. 1(A) shows the internal structure of the liquid crystal display device of this example. 7 is a drive IC for driving the liquid crystal display panel 5; 8 is a passive element chip component such as a capacitor or a resistor; 9 is a TA on which the drive IC 7 is mounted.
B, 10a, 10b, and 10c are made of elastic members such as polyimide, and TAB9. An FPC (flexible printed wiring board) on which 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
1 is a certain 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 etc. through a connector part 6 into data for a TPT liquid crystal display device, 12 is the liquid crystal display panel 5
Input terminals of the liquid crystal display panel 5 provided on the outer periphery of three sides, 1-3 are output terminals of the TAB9 (output side outer leads), and 14 are input terminals of the TAB9 (input side outer leads)
, 5 are output terminals of the FPCs 10a to 10loe.

Reference numeral 25 denotes a plurality of reinforcing plates provided at the connection part of the TAB 9 (location of the output terminal work 5 of the FPC) and the mounting part of the chip component 8 in the FPC 10a-10c. are divided in the longitudinal direction of the FPC, and gaps are provided between each reinforcing plate 25. 26 is a connection part between each FPC 10a to 10c, and each FP
It is provided at both ends of C.

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 drive ICs 7 are arranged around the outer periphery of 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.
10c. F P C 1 0
A to 10c are each attached to the lower shield case 2. For example, small holes 16 penetrating through the 5FPCs 10a to 10c and the reinforcing plate 25 are drilled at several predetermined locations, and by fitting these holes 16 to pins 17 integrally provided on the lower shield case 2, the FPC 1 ．．
Oa~loc 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 drive circuit, and the FPC 1 located at the left
0b is provided with a vertical scanning circuit, and P located on the right
The CB 1 1 is provided with a power supply circuit ps and a CRTnTFT 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)). Please note that there is no FPC on the outer periphery of one side.
The reason for using this is that there is no problem of lead wire breakage as with three-sided FPCs, and there are many mounted components such as power supply circuits and conversion circuits that need to be soldered. However, an FPC and a reinforcing plate may be used instead of the PCB.

Since TAB9 and chip capacitor 8 are thin,
Although they are mounted on the FPC boards 10a to 10c, the power supply circuit PS and conversion circuit CNV are not chip-shaped, but are sealed with plastic or ceramic, and are composed of integrated circuits (ICs) with external leads, transistors, passive components, etc. Because of this, it is thick and is attached to the back side of the PCB 1 1, so that the display surface (top surface) is made as flat as possible.

The chip capacitor 8 is a bypass capacitor for removing lithopulls that is electrically connected to the DC potential wiring from the power supply circuit PS mentioned above, and in order to increase the mounting efficiency,
They are placed in the four corners.

FIG. 1(E) shows an electrical connection between the liquid crystal display panel 5 and the TAB 9, and an electrical connection between the TAB 9 and the Todo IC 7.
Electrical connections between TAB9 and FPC 10a to 10c are shown.

The liquid crystal display panel 5 is composed of a lower transparent glass substrate SUBI and an upper transparent glass substrate SUB2 with the liquid crystal LC as a reference, and the 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 (above the edge of the lower glass substrate SUBI), 13 is an output side outer lead of the TAB 9, 18 is an electrode of the drive IC 7, and 19 is an input terminal of the liquid crystal display panel 5. The inner lead of TAB9, 4 is the input side outer lead of TAB3, and 15 is the output terminal of FPCs 10a to 10c. Note that the input terminal 12 of the liquid crystal display panel 5
As described above, the ends of the scanning signal 1% GL extend in the column direction and are arranged in plurality in the row direction, and the video signal lines DL extend in the row direction and are arranged in plurality in the column direction. is the end of

The input terminal 12 of the liquid crystal display panel 5 and the output side outer lead 13 of the TAB 9 are connected by an anisotropic conductive film 20.

The inner lead 19 of the TAB 9 and the electrode 18 of the drive IC 7 are connected.

TAB9 input side outer lead l4 and FPC10a~1
It is electrically and mechanically connected to the output terminal 15 of 0c by soldering.

Figure 1 (F). , (G), (H) and Figure 1 (I
) according to the cross-sectional view of each F P C 1 0 a ~ 1 0
c is shown. FIG. 1(F) is a plan view showing the signal side FPC 10a, FIG. 1(G) is a plan view showing the scanning side FPCIOb, and FIG. 1(H) is a plan view showing the signal side FPC 10c.

In this embodiment, F, which is the drive wiring section of the liquid crystal display panel 5,
The PC is shown in Fig. 1 (F), (G). As shown in (H),
Three FPCs 10a, 10b, 1 that are independent and separate parts
It is configured at 0c. Each FPC10a~
10c is provided with an input terminal (not shown) and an output terminal 15, and also has a chip component 8 mounted thereon. (F)
, (H) indicate that the terminal surface is on the back side. In addition, each FPC is provided with a hole 16, and a pin 17 (
(See Figure 1, (A)) is inserted so that the FPC is held in the lower shield case 2. 2
Reference numeral 6 denotes a connection section for connecting FPCs together, which will be described in detail later.

FIG. 1(I) is a sectional view of the FPC. 21 is a base film made of polyimide or the like with a certain layer thickness, 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 composed of three polyimide layers, and the connecting parts 26 (Fig. 1 (F) to (H)) of the FPCs are
) 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. 26 is FPC10a~10
27 is a terminal for connecting the FPCIOs a to 10c, and 28 is 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 considered an electrically floating (bloating) terminal. The connecting portion 26 is made up of only the l-layer, that is, the pace film 21 shown in FIG. 1(I), and is flexible.

In the liquid crystal display device of this embodiment, the drive wiring portion of the liquid crystal display panel 5 is made of an elastic material such as polyimide.
10a" 10c, the stress generated in the long axis direction of the FPC due to the difference in expansion coefficient between the liquid crystal display panel 5 and the FPC is transferred to the flexible PFC10.
This is absorbed by the bending of a to 10c, and it is possible to prevent the input side outer lead 14, where the strength of the TAB 9 is the weakest, from being cut, thereby improving the reliability of the liquid crystal display device against heat. In addition, as liquid crystal display screens become larger, as the size of the liquid crystal display device increases, the driving wiring section including the TAB becomes heavier, but since FPCs are lighter than conventional PCBs, the driving wiring section 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.

In addition, reinforcing plates 25 are provided at the connection portions of TAB 9 of FPCs 10a to lOc and the mounting portions of chip components 8.
Since it is reinforced from the back side, it is possible to stably and easily connect the TAB 9 and mount the chip component 8, resulting in good workability. In addition, since the reinforcing plate 25 is divided in the longitudinal direction of the FPCs 10a to 10c, the flexible FPCs 10a to 10
The action of absorbing stress by bending c is effectively carried out.

Furthermore, as shown in Fig.
, and other connecting parts can be omitted, and the number of connecting steps can be reduced by half. In addition, since the connecting portion 26 is composed of only one layer and is highly flexible, it is easy to connect the FPCs 10a to 10c and absorb stress.
By providing this, it is possible to increase the number of terminals to be soldered at the connection portion 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 noise countermeasure.

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.

For example, the mounting method according to the present invention can also be applied to electroluminescent display devices. [Effects of the Invention] As explained above, according to the display device of the present invention, since the driving wiring section of the liquid crystal display panel is made of an elastic material, the liquid crystal display panel and the driving wiring section are made of an elastic material. Since this stress can be alleviated, breakage of the TAB leads can be prevented, and the reliability of the liquid crystal display device against heat can be improved. Furthermore, a compact and highly reliable display device can be provided.

[Brief explanation of drawings]

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 1 (C) is a front view of Figure 1 (B), Figure 1 (D) is a side view of Figure 1 (B), and Figure 1 (E) is a liquid crystal display panel/TAB. Figure 1 (F), (
G) and (H) are flat figures of each FPC, and Figure 1 (1) is
FIG. 1 (J) is a cross-sectional view of the FPC, and FIG. 1 (J) is a plan view showing the connection part of the FPC. FIG. FIG. 3 is a sectional view taken along line nn in FIG. 2, FIG. The figure is a plan view of the main part depicting only the pixel electrode and color filter layer shown in FIG. 4, and FIG. 6 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...Drive IC 8...Chip parts 9...TAB 10a, 10b, 10c-FP C11...
・PCB engineering 2...LCD panel input terminal 13...TAB output side outer lead 14...TA
B input side outer lead 15...FPC output terminal 16...hole 17...pin SUBI...lower transparent glass substrate SUB2...upper transparent glass substrate LC...liquid crystal SL...sealing material 18... Electrode 19 of drive IC... Inner lead 20 of TAB... Anisotropic conductive film 2l... Base film 22... Cover film 23... Conductor 24... Adhesive layer 25 ... Reinforcement plate 26 ... FPC connection part 27 ... FPC terminal 28 ... Dummy terminal

Claims (1)

[Scope of Claims] 1. A liquid crystal display panel, a TAB electrically connected to the liquid crystal display panel and mounting a driving IC for driving the liquid crystal display panel, and a TAB electrically connected to the TAB and mounted with a drive IC for driving the liquid crystal display panel; 1. A display device comprising: a wiring board on which is mounted, the wiring board being made of an elastic member. 2. (1) A vertical signal line extending in the horizontal direction and arranged in a plurality in the vertical direction; a horizontal signal line extending in the vertical direction and arranged in a plurality in the horizontal direction; a display matrix having a third side and opposing second and fourth sides; (2) first and fourth horizontal signal lines for driving the horizontal signal lines disposed on the second and fourth sides; (3) a vertical drive circuit arranged on the third side for driving the vertical signal line; (4) a vertical drive circuit arranged on the first side and arranged on the first and second sides; 1. A display device comprising: two horizontal drive circuits and an interface circuit for operating the vertical drive circuit. 3. The interface circuit includes a power supply circuit for the first and second horizontal drive circuits, the vertical drive circuit, and a circuit for converting an external cathode ray tube display signal into an active matrix liquid crystal display signal. The display device according to claim 2, characterized in that:. 4. Each of the first and second horizontal drive circuits and the vertical drive circuit are attached to a wiring board made of a first material, and the interface circuit is attached to a wiring board made of a second material. 3. The display device according to claim 2, wherein the first material has greater elasticity than the second material. 5. A claim characterized in that the wiring from the interface circuit to the vertical disturbance circuit is arranged so as to be connected to the third wiring board part via the first and second wiring board parts. The display device according to item 4. 6. The display device according to claim 2, further comprising a capacitor disposed at both ends of each of the first and second horizontal drive circuits.