JP2011129554A - Circuit board to which fpc substrate is connected, and method of connecting fpc substrate and circuit board together - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit board to which an FPC substrate is connected, and to provide a method of connecting the FPC substrate and circuit board together such that an electric connection between a connection terminal of the circuit board and a connection terminal of the FPC substrate can be made accurately and speedily without providing any alignment mark. <P>SOLUTION: At least two of connection terminals 20 of the circuit board 15 are made longer in length than other connection terminals 20 to protrude to a wiring formation part side of the circuit board 15 to have surfaces thereof exposed as dummy connection terminals 20a, and the exposed parts of the dummy connection terminals 20 are used as marks to align corresponding connection terminals 24 of the FPC substrate 12 which can be easily viewed in plan view with the dummy connection terminals 20a in plan view. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a circuit board to which a flexible printed circuit (FPC) board is connected and a method for connecting the FPC board and the circuit board. More specifically, the FPC board and the circuit can be provided without providing an alignment mark. The present invention relates to a circuit board to which an FPC board that can be easily and accurately aligned with the board and a method for connecting the FPC board and the circuit board.

Electro-optical display devices include liquid crystal display devices, organic electroluminescence (EL: Elec)
Various types of devices such as tro-Luminescence) display devices, inorganic EL display devices, plasma display devices, electrophoretic display devices, field emission display (FED) devices, and light emitting diode array display devices are known. It has been.

For example, in the case of a liquid crystal display device, these electro-optical display devices include an array substrate provided with pixel electrodes and the like, and a color filter substrate disposed so as to face the substrate (the following patent document) 1). The array substrate is formed to be larger than the color filter substrate when viewed from the front of the display surface, and this one end surface is covered with a resist material for inputting a drive signal to each pixel. A plurality of routing wirings, an IC chip to which the routing wirings are connected, a plurality of wirings electrically connected to the IC chip and having a surface coated with a resist material, and the plurality of wirings. A plurality of exposed connection terminals connected are provided. The plurality of connection terminals are formed on at least one side of the peripheral edge of the array substrate.

Further, in the liquid crystal display device, a drive circuit board is used separately from the array substrate in order to supply driving signals to these connection terminals, but a plurality of exposed connections are also formed on the periphery of the drive circuit board. Terminals are provided. An FPC board is used to electrically connect the array board and the drive circuit board. On the front end side and the rear end side of the FPC board, a connection terminal of the array board and a connection terminal of the drive circuit board are provided. The same number of exposed connection terminals are provided. Thus, the array substrate and the drive circuit substrate are electrically connected via the FPC substrate, and an image signal displayed on the liquid crystal display device is input to the IC chip on the array substrate.

When connecting the connection terminals of the FPC board to the connection terminals of the array board and the drive circuit board, an anisotropic conductive film is provided between the connection terminals of the array board and the drive circuit board and the connection terminal of the FPC board. And the substrates are connected by thermocompression bonding (see Patent Document 2 below). When an anisotropic conductive film is used, the electrical connection between a plurality of terminals formed on the circuit board and the FPC board can be easily performed by one thermocompression bonding as compared with the case of solder connection. , It has the advantage that the flexibility of the connection part and the relaxation of the thermal stress can be achieved.

At this time, what is important is the alignment of the plurality of connection terminals of the circuit board and the plurality of connection terminals of the FPC board. Since the connection terminals of the circuit board and the connection terminals of the FPC board are originally arranged in the same manner, it seems that the positioning of the connection terminals of the circuit board and the connection terminals of the FPC board can be automatically performed automatically. . However, in recent high-definition electro-optical devices, the connection terminals of the circuit board and the connection terminals of the FPC board are both thin and numerous, and the pitch between the terminals is narrow, so that the short-circuit between adjacent terminals with a slight inclination. Will occur.

Furthermore, there are slight variations in each of the connection terminals of the circuit board and the connection terminal of the FPC board, and there is a slight backlash when attaching to the alignment jig. It is difficult to perform accurate alignment. For this reason, alignment is performed manually, but some visible mark is necessary for this alignment.

However, the individual connection terminals on the circuit board to which the FPC board is connected are covered with a semi-transparent anisotropic conductive film and the surface thereof is not exposed to the outside because it is necessary to be electrically insulated. The state is covered with the FPC board. Also, the narrower the pitch between the connection terminals, the more difficult it is to identify individual connection terminals on the circuit board. For this reason, it is difficult to accurately perform alignment using the connection terminal of the circuit board as a mark even if a microscope or the like is used. In addition, since parts other than the connection terminals are coated with a photoresist for electrical insulation, it is difficult to visually recognize the wiring other than the connection terminals, so it is difficult to align the connection terminals. It is.

Therefore, conventionally, when connecting an FPC board to a circuit board using an anisotropic conductive film,
A mark called an alignment mark is used for alignment. This alignment mark indicates a stylized pattern that is placed with exact location on each substrate to facilitate alignment. That is, when an FPC board is electrically connected to a circuit board, for example, an anisotropic conductive film is temporarily fixed to an array board or a drive circuit board of a liquid crystal display device and provided on both left and right ends of the circuit board. The alignment mark is aligned while confirming an enlarged image of the alignment mark portion with a microscope or the like so that the alignment mark matches the alignment marks provided on the left and right ends of the FPC board.

However, alignment work using this alignment mark must be performed easily because it is necessary to visually recognize the alignment marks on the array substrate and the drive circuit substrate through the semitransparent anisotropic conductive film and the translucent FPC substrate. It is not something that can be done. Therefore, the alignment between the circuit board and the FPC board is the least efficient in the manufacturing process of various electro-optical display devices. In addition, even if the alignment is performed using the alignment mark as a mark, the connection terminals are not necessarily 100% surely aligned and connected. That is, although the relative positions of the alignment marks with the connection terminals are aligned, the connection accuracy between the connection terminals is lower than when the connection state of the connection terminals is directly recognized.

JP 2008-233727 A Japanese Patent Laid-Open No. 08-007957

Due to recent demands for miniaturization and high detail of electro-optical display devices, the size of pixels and the number of pixels have increased, and the number of connection terminals has increased accordingly, and the width of connection terminals and connection terminals have increased. The pitch between them is also smaller. Therefore, it is required that the positioning of the connection terminals of each substrate is more precise. However, as described above, the alignment using the alignment mark has a limit in accuracy, and even if there is a room for aligning the alignment mark more accurately, the alignment requires a longer time. There is a problem of becoming. In addition, there is a problem that a space for forming alignment marks must be secured separately between densely arranged wirings and circuits resulting from high definition and miniaturization of the electro-optic display device.

In view of the above-mentioned problems, the present inventors have studied various methods capable of performing quicker and more reliable alignment using a mark instead of an alignment mark as a mark. As a result, the inventors pay attention to so-called dummy connection terminals of the circuit board, and form wiring of the circuit board by making at least two of these dummy connection terminals longer than the other connection terminals. It is found that if the surface of the FPC board is exposed by projecting it to the part side, the connection terminal of the FPC board can be easily seen in a plan view, so that a quick and accurate alignment can be performed using the projecting part of the dummy connection terminal as a mark. The present invention has been completed.

That is, the present invention provides an FPC board that can quickly and accurately align both boards without providing an alignment mark when performing electrical connection between the connection terminals of the circuit board and the FPC board. It is an object of the present invention to provide a connected circuit board and a method for connecting an FPC board and a circuit board.

In order to achieve the above object, a circuit board to which the FPC board of the present invention is connected has a plurality of wirings whose surfaces are coated with an insulating material, and a surface electrically connected to each of the plurality of wirings on one side. A plurality of exposed connection terminals, a circuit board on which is formed;
An FPC board on which a plurality of connection terminals whose surfaces are exposed at one end side is formed;
In a circuit board to which an FPC board in which a plurality of connection terminals of the circuit board and a plurality of connection terminals of the FPC board are electrically connected by an anisotropic conductive film is connected,
The plurality of connection terminals of the circuit board includes at least two dummy connection terminals having a length longer than other connection terminals protruding to the wiring side of the circuit board,
In the plan view, the FPC board is in a state in which a portion protruding to the wiring side of the dummy connection terminal of the circuit board is exposed, and a plurality of other connection terminals of the circuit board are covered with a surface,
It is arranged.

According to the circuit board connected to the FPC board of the present invention, even without the alignment mark,
It is possible to obtain a circuit board to which an FPC board in which connection terminals are securely connected without substantial displacement is connected. That is, since the connection terminal formed on the FPC board is made of an opaque metal, and the base of the FPC board is made of a translucent resin, the connection terminal of the FPC board can be easily seen from the front side of the FPC board. can do. Furthermore, the connection terminals on the circuit board are also formed of an opaque metal, and at least two dummy connection terminals that protrude to the wiring side of the circuit board partially protrude even when the FPC boards are overlaid. It can be easily recognized as distinguished from the wiring coated with the insulating material.

Therefore, when connecting the FPC board to the circuit board, the exposed portions of these dummy connection terminals can be used as marks, and the corresponding connection terminals of the FPC board can be aligned with the exposed portions in a straight line in plan view. A circuit board to which an FPC board in which the connection terminals are accurately aligned is connected is realized. In addition, in plan view, the protruding portion of the dummy connection terminal on the wiring side is in an exposed state, and the plurality of other connection terminals of the circuit board are in a state of covering the surface, so that they are not exposed. In addition, since the dummy connection terminals are normally not connected to each other and are in a floating state, there is no possibility that a short circuit failure will occur even if the surface of the dummy connection terminals is partially exposed.

In the circuit board to which the FPC board of the present invention is connected, the circuit board can be a drive circuit board of an electro-optic display device or a display panel of an electro-optic display device.

In recent years, electro-optic display devices have high definition, so that connection terminals of circuit boards and FP
The connection terminals of the C substrate are thin and many, and the pitch between terminals is also narrow. When the circuit board to which the FPC board of the present invention is connected is applied to the drive circuit board of such an electro-optical display device or the display panel of the electro-optical display device, the above-described effects of the present invention are remarkably exhibited. Examples of the electro-optical device to which the present invention can be applied include a liquid crystal display device, an organic EL display device, an inorganic EL display device, a plasma display device, an electrophoretic display device, an FED device, and a light emitting diode array display device. .

In the circuit board to which the FPC board of the present invention is connected, the electro-optical display device can be a liquid crystal display device or an organic EL display device.

Since the liquid crystal display device and the organic EL display device are particularly downsized and high definition, the connection terminals of the circuit board and the connection terminal of the FPC board are thinner and more numerous than other types of electro-optical devices. Moreover, the pitch between terminals is also narrowed. Therefore, according to the circuit board to which the FPC board of the present invention is connected, the above effect is particularly noticeable.

In the circuit board to which the FPC board of the present invention is connected, at least two dummy connection terminals projecting to the wiring side of the circuit board are dummy connection terminals located on the most end sides of the dummy connection terminals. It is preferable that it contains.

Even when the dummy connection terminal is used as a mark, some errors may occur as long as the alignment mark is used as a mark as in the past as long as the manual connection is used. Considering this point, as the positions of the two marks are closer, the alignment error between the circuit board and the FPC board tends to increase. Therefore, it is possible to perform more accurate alignment when the mark is located as far as possible.

Furthermore, in order to achieve the above object, the method for connecting the circuit board and the FPC board of the present invention includes:
For a circuit board on which a plurality of wirings whose surfaces are covered with an insulating material and a plurality of connection terminals whose surfaces are electrically connected to the plurality of wirings are exposed on one side. After aligning an FPC board in which a plurality of connection terminals corresponding to each connection terminal of the board are formed on one end of the FPC board so that the corresponding connection terminals overlap with an anisotropic conductive film interposed therebetween, the circuit A method of connecting an FPC board and a circuit board, wherein the board and the FPC board are connected by thermocompression bonding.
In the alignment,
As the circuit board, use what is formed with at least two dummy connection terminals that are longer than the other connection terminals protruding to the wiring side of the circuit board,
The connection terminals of the FPC board corresponding to the dummy connection terminals are aligned with the portions of the dummy connection terminals protruding to the wiring side in a plan view, and the connection terminals of the circuit board and the FPC board are aligned. It is characterized by positioning with the connection terminal.

The connection terminals formed on the FPC board are made of an opaque metal, and the base of the FPC board is made of a translucent resin, so that the connection terminals of the FPC board can be easily formed even from the base side of the FPC board. Can be visually recognized. In addition, the dummy connection terminal on the circuit board is also formed of an opaque metal, and the dummy connection terminal protrudes even when the FPC board and the circuit board are overlapped with each other. It can be easily visually recognized by distinguishing from the wiring. Therefore, according to the method for connecting the FPC board and the circuit board of the present invention, even if no alignment mark is provided, the exposed connecting portion of the dummy connecting terminal is used as a mark, and the corresponding connecting terminal of the FPC board is seen in a plan view. Thus, it is possible to easily perform accurate alignment in the left-right direction by performing alignment so as to be continuous in a straight line.

Even when the FPC board is inclined with respect to the circuit board, the exposed portion of the dummy connection terminal is used as a mark, and the corresponding connection terminal of the FPC board is aligned with the exposed portion in a straight line in plan view. As a result, the inclination of the FPC board relative to the circuit board can also be corrected. At the same time, the dummy connection terminals are partially exposed, and the connection terminals of other circuit boards are aligned so as to be covered with the FPC board, thereby facilitating accurate vertical alignment. Will be able to do.

It is a schematic plan view which shows the connection state of the circuit board and FPC board which concern on embodiment of this invention. FIG. 2 is an enlarged plan view of a region II part in FIG. 1. 3A is a schematic cross-sectional view taken along line IIIA-IIIA in FIG. 2, and FIG. 3B is a schematic cross-sectional view taken along line IIIB-IIIB in FIG. It is the schematic which looked at the principal part of the crimping machine containing the stage in which the array board | substrate was mounted from the side. It is explanatory drawing which shows the method of aligning a FPC board | substrate with respect to an array board | substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the embodiment shown below shows an example applied to a liquid crystal display panel and a driving circuit board of the liquid crystal display panel as an example of a circuit board in order to embody the technical idea of the present invention. The invention is not intended to be specific to the liquid crystal display panel or the drive circuit board of the liquid crystal display panel, and other embodiments within the scope of the claims are equally applicable.

First, a liquid crystal display device as an electro-optical display device to which the present invention is applied will be described with reference to FIGS. As shown in FIGS. 1 and 2, the liquid crystal display device 10 includes a liquid crystal display panel 11 corresponding to the circuit board of the present invention, an FPC board 12 connected to the liquid crystal display panel 11, and also connected to the FPC board 12. And a drive circuit board 13 corresponding to another circuit board of the present invention.

The liquid crystal display panel 11 includes a color filter substrate 14 and an array substrate 15 formed so that one end surface projects from the display surface side of the color filter substrate 14.
A plurality of routing lines 16 covered with a resist material for inputting a drive signal to each pixel in the display area, and an IC chip 17 to which these routing lines 16 are connected, are arranged on one end face of the array substrate 15 protruding. A plurality of connection wires 19 covered with a resist material 18 electrically connected to the IC chip 17 and a terminal region 21 in which a plurality of exposed connection terminals 20 (see FIG. 2) are formed. It has been. The terminal region 21 in which the plurality of connection terminals 20 are formed is aligned on one short side of the array substrate 15, for example.

The drive circuit board 13 is formed with a peripheral circuit (not shown) for generating various signals such as an image signal and a clock signal output to the liquid crystal display panel 11, and a plurality of connections are formed on one short side thereof. A terminal region 22 in which terminals (not shown) are aligned is formed. The connection terminals 20 in the terminal area 21 of the array substrate 15 and the connection terminals in the terminal area 22 of the drive circuit board 13 are electrically connected to each other by the FPC board 12.

As shown in FIG. 3B, the FPC board 12 is attached to one end of a flexible translucent board 23.
A plurality of connection terminals 24 for electrical connection with the connection terminals 20 formed in the terminal region 21 of the array substrate 15 are arranged in alignment, and formed at the connection portion 22 of the drive circuit board 13 at the other end. A plurality of connection terminals (not shown) for electrical connection with the connection terminals are formed. The plurality of connection terminals 24 on one end side of the FPC board 12 and the plurality of connection terminals on the other end side are electrically connected to each other by connection wirings 25, and the surface of the connection wiring 25 is formed of a resist material or an insulating material. It is covered with a translucent thin film 26 made of

FIG. 2 is an enlarged plan view of a region II portion of FIG.
It is a figure which shows the connection state between the connection terminals 24 of C board | substrate 12 in detail. 2 illustrates a plurality of connection terminals 20 of the array substrate 15 and a plurality of connection terminals 24 of the FPC substrate 12 superimposed on the array substrate 15, which are not illustrated in FIG.

The connection terminals 20 of the array substrate 15 are all formed with the same width and the same pitch, and all of them have the same length, except for three dummy connection terminals 20a in total at three ends, respectively. Yes. However, the six dummy connection terminals 20a at both ends are slightly longer than the other connection terminals. Further, all the routing wirings 16 and connection wirings 19 of the array substrate 15 are covered with a resist material 18 and insulated from each other. The dummy connection terminal 20a is not covered with the resist material 18, and the surface is exposed.

The dummy connection terminal 20a is not electrically connected to any of the array substrate 15 and is in a floating state. When dummy terminals are formed on the IC chip 17, the dummy connection terminals 20 a may be electrically connected to the dummy terminals of the IC chip 17. In this case, the dummy terminal of the IC chip 17 and the array substrate 1
It is preferable that the surface of the connection wiring (not shown) connecting the five dummy connection terminals 20 a is covered with a resist material 18.

The plurality of connection terminals 24 of the FPC board 12 have the same length, the same width, and the same pitch. The plurality of connection terminals 24 of the FPC board 12 are substantially connected to the array board 15.
The width and pitch of the connection terminals 20 are the same as those of FIG. 2, but are slightly wider than the connection terminals 20 of the array substrate 15 in FIG. Further, the plurality of connection terminals 24 of the FPC board 12 are formed in a number corresponding to the connection terminals 20 and the dummy connection terminals 20a of the array board, respectively.

A fixed state of the connection terminals 20 of the array substrate 15 and the connection terminals of the FPC substrate 12 will be described with reference to FIG. 3A is a cross-sectional view taken along line IIIA-IIIA in FIG. 2, and FIG. 3B is a cross-sectional view taken along line IIIB-IIIB in FIG. As shown in FIG. 3A, an anisotropic conductive film 27 is placed on the dummy connection terminal 20 a of the array substrate 15, and the dummy of the array substrate 15 is interposed via the anisotropic conductive film 27. The connection terminals 20a are electrically connected to the connection terminals 24 of the FPC board 12, respectively. The surface of the dummy connection terminal 20a on the IC chip 17 side is partially exposed, but the surfaces of the other dummy connection terminals 20a and the connection terminals 20 are the connection terminals 24 of the FPC board 12 and the translucent substrate 23. It is covered by.

As shown in FIG. 3B, an anisotropic conductive film 27 is also placed on the connection terminals 20 of the array substrate 15, and the array substrate 15 is interposed via the anisotropic conductive film 27.
The connection terminals 20 are electrically connected to the connection terminals 24 of the FPC board 12, respectively. The surface of the dummy connection terminal 20a on the side of the IC chip 17 is partially exposed, but the other surface is covered by the connection terminal 24 of the FPC board 12 and the translucent substrate 23 via the anisotropic conductive film 27. It is covered.

Such a connection terminal 20 or dummy connection terminal 20a of the array substrate 15 and the FPC substrate 1
A connection method between the two connection terminals 24 will be described with reference to FIGS. FIG. 4 is a schematic view of the main part of the crimping machine including the stage on which the array substrate is placed as seen from the side. Also,
FIG. 5 is an explanatory diagram showing a method of aligning the FPC board with respect to the array board.

First, the array substrate 15 is positioned and placed on the positioning jig (mounting table) 30. Note that any well-known configuration can be adopted as the means for positioning. Then, an anisotropic conductive film is temporarily fixed to the array substrate 15 with a tape or the like,
The FPC board 12 is aligned with the array board 15. The alignment at this time is
For example, this is performed by using the TV camera 31 and finely adjusting the position and arrangement of the FPC board 12 by hand while viewing an enlarged image displayed on a monitor (not shown).

The monitor displays a planar image of the connection portion (terminal region 21) between the array substrate 15 and the FPC substrate 12 as viewed from above. At this time, since the connection terminal 24 of the FPC board 12 is opaque, it can be clearly seen through the translucent board 23 of the FPC board 12. On the other hand, a part of the dummy connection terminals 20a of the array substrate 15 and the connection terminals 20 are completely covered with the anisotropic conductive film and the FPC board 12, so that it is very difficult to see. However, the surface of the dummy connection terminal 20a on the IC chip 17 side is partially exposed, and the portion where the surface of the dummy connection terminal 20a is exposed is the FPC board 12 and the resist material 1.
Since it is not covered with 8, it is easily visible.

Therefore, in the present embodiment, the FPC board 12 is aligned so that the exposed portion of the dummy connection terminal 20a projected on the monitor and the connection terminal 24 of the FPC board 12 overlap and form a straight line. In this way, accurate alignment can be performed. At the time of this alignment, when the connection terminal 20 of the array substrate 15 and the connection terminal 24 of the FPC substrate 12 are stacked in an inclined state, the connection of the array substrate 15 is performed while intersecting between the connection terminals 24 of the FPC substrate 12. The terminal 20 can be visually recognized, and in some cases, moire fringes are observed. Therefore, it can be easily confirmed that the connection terminals 20 of the array substrate 15 and the connection terminals 24 of the FPC board 12 are inclined. In such a case, if the degree of exposure of the dummy connection terminals 20a formed on both ends of the array substrate 15 is approximately the same so that the moire fringes are not visible,
The connection terminals 20 of the array substrate 15 and the connection terminals 24 of the FPC board 12 can be easily adjusted to be in a straight line.

Further, as shown in FIG. 5A, when none of the connection terminals 20 including the dummy connection terminals 20a of the array substrate 15 is visible from the FPC board 12 side, the dummy connection terminals 20a at both ends of the array substrate 15 are The other connection terminal 20 is completely FP so that it can be visually recognized.
Positioning can be accurately performed by moving the FPC board 12 downward so that it cannot be visually recognized by being covered with the C board 12. Conversely, as shown in FIG. 5B, when both the connection terminal 20 and the dummy connection terminal 20 b of the array substrate 15 are visible from the FPC board 12, the dummy connection terminals 20 a at both ends of the array substrate 15. So that the other connecting terminals 20 are completely covered with the FPC board 12 and cannot be visually recognized.
By moving the PC board 12 upward, alignment can be performed accurately.

Further, as shown in FIG. 5C, the connection terminals 20 of the array substrate 15 are completely covered, and a part of the dummy connection terminals 20a on both ends of the array substrate 15 is exposed and visible. When the corresponding connection terminal 24 of the FPC board 12 is shifted to the right side with respect to the exposed portion of the dummy connection terminal 20a of the board 15, the FPC board 12 is shifted to the left side so that the array board 15 is exposed. If the corresponding connection terminals 24 of the FPC board 12 are connected to the dummy connection terminals 20a in a straight line, the alignment can be performed accurately. vice versa,
As shown in FIG. 5D, the connection terminals 20 of the array substrate 15 are completely covered, and part of the dummy connection terminals 20a on both ends of the array substrate 15 are exposed and visible.
If the corresponding connection terminal 24 of the PC board 12 is shifted to the left side, the FPC board 12 is shifted to the right side and the exposed dummy connection terminal 20a of the array board 15 is connected to the FPC board 12.
When the corresponding connection terminals 24 are arranged in a straight line, alignment can be performed accurately.

Thus, using the exposed portion of the dummy connection terminal 20a of the array substrate 15 as a mark, the FPC
If the substrate 12 is moved up and down, left and right, and further rotated left and right as necessary, the connection terminals 20 of the array substrate 15 and the corresponding connection terminals 24 of the FPC substrate 12 are directly visually recognized without using alignment marks. And can be aligned.

After this alignment, the connection portions 20 of the array substrate 15 and the dummy connection terminals 20a and the FPC substrate 12 are bonded via an anisotropic conductive film by thermocompression bonding of the connection portions of the array substrate 15 and the FPC substrate 12. The connection terminals 24 are accurately aligned and electrically connected.

In the above-described embodiment, three dummy connection terminals 20a of the array substrate 15 are provided at both ends. However, the tip portion of the array substrate 15 is exposed in a state where the array substrate 15 and the FPC substrate 12 are overlapped. Two or more dummy connection terminals 20a may be provided, and the positions thereof are not particularly limited to both ends. However, as the exposed dummy connection terminal 20a is further away, more accurate alignment is possible. Therefore, it is desirable to select the dummy terminals 20a at both ends, and the dummy terminals at both ends and the dummy terminals adjacent thereto are selected. More preferably, the total is 4 or more.

In the above embodiment, the example in which the array substrate of the liquid crystal display device and the FPC substrate are connected is shown. However, the circuit substrate to which the FPC substrate of the present invention is connected is not limited to this, and the drive circuit substrate and the FPC are connected. The present invention can be applied to connection between various circuit boards and FPC boards, including cases where boards are connected. For example, as long as it is limited to an electro-optical display device, it can be applied to various types such as an organic EL display device, an inorganic EL display device, a plasma display device, an electrophoretic display device, an FED device, and a light emitting diode array display device.

DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display device 11 ... Liquid crystal display panel 12 ... FPC board 13 ... Drive circuit board 14 ... Color filter board 15 ... Array board 16 ... Lead-out wiring 17 ... IC chip 18 ... Resist material 19 ... Connection wiring 20 (array board) ... (of array substrate)
Connection terminal 20a ... Dummy terminal 21 ... Terminal area of (array substrate) 22 ... Terminal area of (drive circuit board) 23 ... Translucent substrate 24 ... Connection terminal of FPC board 25 ... (FP)
Connection wiring 26 of C substrate 26 ... Translucent thin film 27 ... Anisotropic conductive film 30 ... Positioning jig (mounting table) 31 ... TV camera

Claims (5)

A circuit board on which a plurality of wirings whose surfaces are covered with an insulating material, and a plurality of connection terminals each having a surface electrically connected to the plurality of wirings on one side are exposed;
Provided with a flexible printed wiring board on which a plurality of connection terminals whose surfaces are exposed at one end are formed,
In the circuit board to which the flexible printed wiring board in which the plurality of connection terminals of the circuit board and the plurality of connection terminals of the flexible printed wiring board are electrically connected by an anisotropic conductive film is connected,
The plurality of connection terminals of the circuit board includes at least two dummy connection terminals having a length longer than other connection terminals protruding to the wiring side of the circuit board,
The flexible printed wiring board is arranged in a plan view, with a portion protruding to the wiring side of the dummy connection terminal of the circuit board exposed and a plurality of other connection terminals of the circuit board covering the surface. A circuit board to which a flexible printed wiring board is connected. The circuit board to which the flexible printed wiring board according to claim 1 is connected, wherein the circuit board is a driving circuit board of an electro-optical display device or a display panel of an electro-optical display device. The circuit board to which the flexible printed wiring board according to claim 2 is connected, wherein the electro-optic display device is a liquid crystal display device or an organic electroluminescence display device. 2. The at least two dummy connection terminals projecting toward the wiring side of the circuit board include dummy connection terminals located on both ends of the front dummy connection terminals.
A circuit board to which the flexible printed wiring board according to any one of to 3 is connected. For a circuit board on which a plurality of wirings whose surfaces are covered with an insulating material and a plurality of connection terminals whose surfaces are electrically connected to the plurality of wirings are exposed on one side. After positioning a plurality of flexible printed wiring boards formed with a plurality of connection terminals corresponding to each connection terminal of the substrate, so that the corresponding connection terminals overlap each other with an anisotropic conductive film interposed therebetween, The circuit board and the flexible printed wiring board are connected by thermocompression bonding the circuit board and the flexible printed wiring board.
In the alignment,
As the circuit board, use what is formed with at least two dummy connection terminals that are longer than the other connection terminals protruding to the wiring side of the circuit board,
The connection terminal of the flexible printed wiring board corresponding to the dummy connection terminal is aligned with the portion of the dummy connection terminal protruding to the wiring side in a plan view, and the connection terminal of the circuit board and the flexible terminal are aligned. A method for connecting a circuit board and a flexible printed wiring board, characterized in that alignment with a connection terminal of the printed wiring board is performed.

Images