JP2001085812A - Substrate connecting structure and optoelectronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a substrate connecting structure, in which a pair of substrates are connected to each other through connecting terminals to maintain the planar shapes of the substrates in small sizes, even when the number of the connecting terminals increases. SOLUTION: A substrate connecting structure 15 is constituted, by connecting a pair of substrates 8 and 10 respectively provided with connecting terminals 24a-24c and 26a-26c to each other via the terminals 24a-24c and 26a-26c. The terminals 24b and 24c and 26b and 26c are formed in the internal regions of the substrates 8 and 10, respectively, and when the terminals 24b and 24c are connected to the terminals 26b and 26c, respectively, the substrates 8 and 10 can be connected to each other in an overlapping state. Since the widths of the side edge sections of the substrate 8 and 10 are not required to be enlarged, the planar shapes of the substrates 8 and 10 can be maintained in small sizes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate connection structure formed by connecting a plurality of substrates, and an electro-optical device constituted by using the substrate connection structure.

[0002]

2. Description of the Related Art At present, electro-optical devices using various materials as electro-optical materials are known. For example, a liquid crystal device using liquid crystal as an electro-optical material, an optical device using an electroluminescence (EL) element including a light emitting polymer as an electro-optical material, or a non-electroluminescent material such as a phosphor or xenon. Various electro-optical devices such as a plasma display (PDP) using an active gas and an optical device using a field emission device (FED) as an electro-optical material are known.

In the above-described electro-optical device, for example, various electro-optical materials are supported by a substrate (hereinafter referred to as a panel substrate), and a substrate connection structure for supplying power or an electric signal to the electro-optical material, for example. Is connected to the panel substrate. The term "substrate connection structure" used herein refers to a structure in which a pair of substrates each having a connection terminal are connected to each other via the connection terminals.

Considering a liquid crystal device as an example of an electro-optical device, a liquid crystal device having a structure shown in FIG. 6 is known as a conventional liquid crystal device. This conventional liquid crystal device has L
A liquid crystal panel 54 is mounted on a light emitting side surface of a light guide 53 having a light emitting source 52 such as an ED, and a third wiring board 60 is mounted on an opposite surface of the light guide 53, that is, a non-light emitting side surface. , A pair of substrates 57 constituting the liquid crystal panel 54
Both the first wiring board 58 connected to one of the first and second wiring boards 57a and 57b and the second wiring board 59 connected to the other of the first and second wiring boards 58b and 59b are bent to the rear side, and these wiring boards 58 and 59 are bent.
The connection terminals 55 formed at the side edges of the third wiring board 60
The connection terminals 56 provided on the back surface of the substrate are connected by a conductive connection process such as soldering.

In this liquid crystal device, a substrate connection structure is formed by connecting the first wiring substrate 58 and the third wiring substrate 60 via the connection terminals 55 and 56.
The connection terminal 5 is connected between the second wiring board 59 and the third wiring board 60.
By connecting via 5 and 56, another substrate connection structure is formed.

[0006]

However, in the above-described conventional board connection structure, the positions of the connection terminals 55 provided on the first wiring board 58 and the second wiring board 59 are set at the side edges of those boards. I was In this case, there is no particular problem when the number of the connection terminals 55 is small, but when the number of the connection terminals 55 is large for performing high-definition display or color display by the liquid crystal panel 54, The dimension in the width direction of the side end portions of the first wiring board 58 and the second wiring board 59, that is, the dimension in the XX direction must be increased, and as a result, the planar shapes of the boards 58 and 59 must be enlarged. There was a problem of not getting.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is intended to reduce the planar shape of a pair of substrates even when the number of connection terminals for connecting the pair of substrates increases. The aim is to be able to keep it small.

[0008]

Means for Solving the Problems (1) In order to achieve the above object, a substrate connection structure according to the present invention comprises a pair of substrates, each having a connection terminal, connected to each other via the connection terminals. In the substrate connection structure formed by connection, the connection terminals formed on the pair of substrates are respectively formed in internal regions other than the side edges of the substrate, and by connecting these connection terminals to each other, It is characterized in that a pair of substrates are connected to each other while being superposed on each other.

According to the substrate connection structure of this configuration, the connection terminals are formed not only at the edge of the substrate but also in the internal region, so that the number of the connection terminals is increased. In such a case, it is not necessary to increase the width of the side edge of the substrate, so that the planar shape of the substrate can be kept small.

(2) In the substrate connection structure according to the above (1), one of the pair of substrates may be a flexible substrate, and the other of the pair of substrates may be a non-flexible substrate. be able to. As a flexible substrate, for example, T
A TCP (Tape Carrier Package) formed using AB (TAB: automated tape mounting) technology can be considered.
Further, as the non-flexible substrate, for example, a substrate using a glass epoxy resin having a suitable thickness as a base layer can be considered.

(3) In the substrate connection structure according to the above (2), an IC chip is mounted on the flexible substrate, and connection terminals connected to the IC chip are provided inside the flexible substrate. It can be configured to be formed in a region. In this case, the connection terminal electrically connects the input terminal or output terminal of the IC chip mounted on the flexible substrate to the output terminal or input terminal of an appropriate circuit formed on the non-flexible substrate. It acts to connect. According to the configuration described in the item (3), the substrate structure including the IC chip and the associated circuit can be formed very small.

(4) In the substrate connection structure described in the above (3), a plurality of IC chips are mounted on the flexible substrate, and connection terminals connected to the IC chips are located at intermediate positions between the IC chips. Can be arranged. At the same time, a plurality of openings for accommodating the plurality of IC chips can be formed in the non-flexible substrate, and connection terminals can be formed at intermediate positions between the openings. Further, the substrates are overlapped with each other so that the IC chip on the flexible substrate is accommodated in the opening on the non-flexible substrate, and the connection terminals are connected to each other in this state. Can be connected. According to this configuration, a substrate structure including a plurality of IC chips and circuits associated therewith can be formed very small.

(5) Next, in the electro-optical device according to the present invention, at least one panel substrate supporting the electro-optical material, a substrate connected to the panel substrate, and another substrate connected to the substrate In the electro-optical device, the pair of substrates are connected to each other via connection terminals provided on each of the pair of substrates, wherein the connection terminals formed on the pair of substrates are respectively edge portions of the substrates. It is characterized in that the pair of substrates are connected to each other by being formed in an internal region other than the above, and by connecting these connection terminals to each other.

According to this electro-optical device, the connection terminals are formed not only at the side edges of the substrate but also in the internal region, so that the number of connection terminals increases. However, it is not necessary to increase the width of the side edge of the substrate, so that the planar shape of the substrate can be kept small. Therefore, the planar shape of the electro-optical device itself can be reduced.

The items described in the above items (2) to (4) can be similarly applied to the electro-optical device described in the above item (5).

That is, in the electro-optical device according to the above mode (5), one of the pair of substrates may be a flexible substrate, and the other of the pair of substrates may be a non-flexible substrate. Can be. As a flexible substrate, for example,
A TCP (Tape Carrier Package) formed using TAB (TAB: automated tape mounting) technology is conceivable. Further, as the non-flexible substrate, for example, a substrate using a glass epoxy resin having a suitable thickness as a base layer can be considered.

When a flexible substrate is used as the substrate in the electro-optical device according to the above mode (5), an IC chip is mounted on the flexible substrate, and connection terminals connected to the IC chip are provided. It can be configured to be formed in an internal region of the flexible substrate. In this case, the connection terminal electrically connects the input terminal or output terminal of the IC chip mounted on the flexible substrate to the output terminal or input terminal of an appropriate circuit formed on the non-flexible substrate. It acts to connect. According to the configuration described here, the substrate structure including the IC chip and the accompanying circuit can be formed very small.

Further, in the electro-optical device according to the above mode (5), when a flexible substrate is used as a substrate and an IC chip is mounted on the flexible substrate, a plurality of ICs are mounted on the flexible substrate. Chips can be mounted, and connection terminals connected to those IC chips can be arranged at intermediate positions between the IC chips. At the same time, a plurality of openings for accommodating the plurality of IC chips can be formed in the non-flexible substrate, and connection terminals can be formed at intermediate positions between the openings. Further, the substrates are overlapped with each other so that the IC chip on the flexible substrate is accommodated in the opening on the non-flexible substrate, and the connection terminals are connected to each other in this state. Can be connected. According to this configuration, a substrate structure including a plurality of IC chips and associated circuits can be formed very small.

(6) In the electro-optical device according to the above (5), the electro-optical material may be a liquid crystal,
Further, the panel substrate may be a pair of substrates for sealing and supporting the liquid crystal. This configuration corresponds to a so-called liquid crystal device. In this liquid crystal device, a voltage applied to liquid crystal provided in a plane region having a predetermined area is partially changed for each dot or for each predetermined pattern, and the liquid crystal device is configured to perform the above-described operation. Is changed, thereby modulating the light passing through the portion to display an image such as a character, a numeral, or a figure outside the pair of substrates.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a substrate connection structure and an electro-optical device according to the present invention will be described with reference to a liquid crystal device as an example. FIG. 1 shows an embodiment of the liquid crystal device. As shown in FIG. 3, the liquid crystal device 1 includes an LED as a light source.
It is formed by attaching a liquid crystal panel 4 to a light emitting surface of a light guide 3 having a (Light Emitting Diode) 2. The liquid crystal panel 4 is bonded to the light guide 3 by, for example, an adhesive 6 provided around the light emitting surface of the light guide 3. Light guide 3
Can be replaced with a light reflecting plate, in which case the light reflecting plate is attached to the back surface of the liquid crystal panel 4, that is, the lower surface of FIG.

The liquid crystal panel 4 has a first substrate 7a and a second substrate 7b, which are a pair of substrates facing each other as a panel substrate, and these substrates are joined to each other by a sealant 14 around them. In FIG. 5, for example, a first electrode 17a serving as a common electrode is formed in a predetermined pattern on a liquid crystal side surface of a substrate material 16a constituting the first substrate 7a, that is, a surface facing the second substrate 7b. An overcoat layer 18a is formed thereon, and an alignment film 19a is further formed thereon. Further, a polarizing plate 21a is attached to the outer surface of the substrate material 16a.

On the liquid crystal side surface of the substrate material 16b constituting the second substrate 7b facing the first substrate 7a, that is, on the surface facing the first substrate 7a, for example, a second electrode 17b acting as a segment electrode is provided at a predetermined position. A pattern is formed, an overcoat layer 18b is formed thereon, and an alignment film 19b is further formed thereon. Also, the substrate material 16b
A polarizing plate 21b is adhered to the outer surface of.

Each of the alignment films 19a and 19b is subjected to a rubbing process for giving the orientation. Further, the polarization axis of the polarizing plate 21a and the polarization axis of the polarizing plate 21b are opposed to each other at a predetermined angle in order to obtain the polarization transmittance required for displaying a visible image. When performing color display, the first substrate 7a and the second substrate 7
A color filter (not shown) is provided on any one of b.

The first electrode 17a and the second electrode 17b are formed of a light transmitting material such as ITO (Indium Tin Oxide) to a thickness of about 1000 angstroms, and the overcoat layers 18a and 18b are formed of, for example, silicon oxide. 80 with titanium oxide or a mixture thereof
The alignment films 19a and 19b are formed to a thickness of about 800 angstroms using, for example, a polyimide resin.

As shown in FIG. 3, the first electrode 17a is formed in a so-called stripe shape by arranging a plurality of linear patterns in parallel with each other, while the second electrode 17b intersects the first electrode 17a. By arranging a plurality of linear patterns in parallel to each other as described above, they are also formed in a stripe shape. A plurality of points where these electrodes 17a and 17b intersect in a dot matrix form pixels for displaying an image. The area defined by the plurality of pixels is a display area for displaying an image such as a character.

The first substrate 7a formed as described above
As shown in FIG. 5, a plurality of spacers 22 are dispersed on one of the liquid crystal side surfaces of the second substrate 7b and a sealing material 14 is further formed on the liquid crystal side surface of one of the substrates by, for example, printing. It is provided in a frame shape as shown in FIG.
Further, a liquid crystal injection port 14a is formed in a part of the sealing material 14.

A spacer 22 is provided between the substrates 7a and 7b.
A gap having a uniform dimension, for example, a dimension of about 5 μm, that is, a so-called cell gap is formed, and the liquid crystal 23 is injected into the cell gap through the liquid crystal injection port 14a. After the injection is completed, the liquid crystal injection port 14a is closed. It is sealed with a resin or the like.

In FIG. 3, the first substrate 7a is the second substrate 7
The first electrode 17a on the first substrate 7a extends directly to the substrate overhang 7c to serve as a connection terminal. Also, the second substrate 7
b has a substrate overhang 7d projecting outside the first substrate 7a, and the second electrode 17b on the second substrate 7b extends directly to the substrate overhang 7d to serve as a connection terminal.

In practice, a large number of electrodes 17a and 17b are formed at substantially very small intervals over substantially the entire surface of the respective substrates 7a and 7b. However, in FIG. These electrodes and the like are schematically illustrated at wider intervals, and some of the electrodes are not illustrated. Further, the electrodes 17a and 17b are not limited to being formed in a stripe shape, that is, a linear shape, but may be formed in an appropriate pattern shape.

In FIG. 3, a board connection structure 15 formed by connecting the first wiring board 8 and the third wiring board 10 is connected to the board extension 7c of the first board 7a. Also, the second
The second wiring board 9 is connected to the board extension 7d of the board 7b. The connection between the first wiring board 8 and the board 7a and the connection between the second wiring board 9 and the board 7b are, for example, ACF (Anisot).
ropic Conductive Film).

As is well known, the ACF is a conductive polymer film used for electrically connecting a pair of terminals with anisotropy, for example, thermoplastic or thermosetting. It is formed by dispersing a large number of conductive particles in a conductive resin film.

The first wiring board 8 is made of, for example, TAB (Tape A).
It is configured as a flexible TCP (Tape Carrier Package) formed using the technology of utomated bonding (automated tape mounting), and as shown in FIG. 4, a flexible base layer 11 made of polyimide or the like is formed. A wiring pattern 12 made of copper or the like is formed thereon, and liquid crystal driving ICs 13a and 13b as IC chips are mounted at two positions where the tips of the wiring pattern 12 gather, for example, by gang bonding.

Further, the second wiring board 9 is composed of the first wiring board 8
It is configured as a flexible TCP similarly to the above, and is configured by the base layer 11, the wiring pattern 12, and the liquid crystal driving IC 13c. The wiring pattern 12 formed on the first wiring substrate 8 is connected to the terminals of the liquid crystal driving ICs 13 a and 13 b, that is, the bumps are connected to the first electrodes 17 in the liquid crystal panel 4.
It has the effect of connecting to a. The wiring pattern 12 formed on the second wiring board 9 has an effect of connecting the bump of the liquid crystal driving IC 13c to the second electrode 17b in the liquid crystal panel 4.

Although a large number of wiring patterns 12 are actually formed on the surfaces of the first wiring substrate 8 and the second wiring substrate 9 at extremely narrow intervals, the structure is shown in FIG. 2 schematically shows the wiring patterns 12 at intervals wider than the actual intervals.

A plurality of, in this embodiment, two liquid crystal driving ICs 13a and 13b on the first wiring substrate 8 are arranged side by side in a direction toward a pair of substrates 7a and 7b. The ICs 13a and 13b are arranged side by side in the direction toward the pair of substrates 7a and 7b such that the longitudinal directions of the ICs 13a and 13b are substantially parallel to each other.

The connection terminals 2 are provided at the side edges of the first wiring board 8.
4a is formed. The connection terminals 24b and the connection terminals are located on the surface of the first wiring board 8 and between the liquid crystal driving IC 13a and the liquid crystal driving IC 13b, that is, in an internal region other than the side edge of the first wiring board 8. 24c are formed substantially parallel to each other. Further, a connection terminal 24d is formed at an edge of the second wiring board 9.

The third wiring substrate 10 is mounted on the surface of the first wiring substrate 8 on the side on which the liquid crystal driving ICs 13a and 13b are mounted, whereby the substrate connection structure 15 is formed. The third wiring substrate 10 includes the liquid crystal driving ICs 13a and 13
This is a wiring board on which a circuit for supporting b and 13c is mounted, and is manufactured by patterning necessary circuits on the surface of a non-flexible substrate material made of, for example, epoxy resin.

On the surface of the third wiring substrate 10 opposite to the surface facing the first wiring substrate 8, that is, on the upper surface of FIG.
A connection terminal 26d is formed, and one end of a wiring cable 27 as an electric connection member for making an electric connection with an external circuit is connected to a side end of the connection terminal. A chip component 29 such as a resistor and a capacitor is provided.

The first wiring board 8 of the third wiring board 10
4, that is, on the lower surface of FIG. 4, the connection terminal 2 is provided in an internal region other than the side edge of the third wiring board.
6a, 26b, 26c are formed, and these connection terminals 26a, 26b, 26c are formed at positions corresponding to the connection terminals 24a, 24b, 24c formed on the first wiring board 8, respectively.

As shown in FIG. 3, the first wiring board 8 and the third wiring board 10 are machined by soldering the connection terminals 24a, 24b, 24c to the connection terminals 26a, 26b, 26c, respectively. Are superimposed on each other and connected. At the same time, the first wiring board 8
Upper wiring pattern 12 and liquid crystal driving ICs 13a and 13b
And the circuit on the third wiring board 10 is electrically connected.

At positions corresponding to the liquid crystal driving ICs 13a and 13b mounted on the first wiring board 8 of the third wiring board 10, an opening 28 larger than those ICs is formed in advance. When the third wiring board 10 is connected to the first wiring board 8 by being overlapped, a liquid crystal driving IC
13a and 13b are accommodated in the openings 28. That is, the opening 28 is provided in the liquid crystal driving IC 1.
The first wiring board 8 and the third wiring board 1 serve as openings for escaping 3a and 13b.
0 can reduce the thickness of the laminated structure.

As described above, the first wiring board 8 and the third
When the substrate connection structure 15 including the wiring substrate 10 and the second wiring substrate 9 are connected to the liquid crystal panel 4, the liquid crystal panel 4 is bonded to the light emitting surface side of the light guide 3 by the adhesive 6. Thereafter, the board connection structure 15 including the first wiring board 8 and the third wiring board 10 is bent toward the back side of the light guide 3 as shown by the arrow A, that is, toward the non-light-emitting surface.
The wiring board 9 is bent on the back side of the light guide 3 and onto the previously bent third wiring board 10 as shown by the arrow B.

FIG. 2 shows the liquid crystal device 1 in a state where the first wiring board 8, the second wiring board 9 and the third wiring board 10 are bent toward the non-light-emitting surface side of the light guide 3 as described above. The state seen from the non-light emitting surface side of the light body 3 is shown. As shown in the figure, the second wiring board 9 is formed by soldering the connection terminals 24d formed at the side edges to the connection terminals 26d formed in the internal region of the third wiring board 10. Connected mechanically and electrically.

As described above, the liquid crystal device 1 according to the present embodiment
When this is viewed from the front side, that is, from the liquid crystal display side, the state shown in FIG. 1 is obtained. In the liquid crystal device 1 of the present embodiment configured as described above, light is supplied from the light emitting surface of the light guide 3 to the liquid crystal panel 4 when the LED 2 emits light.

In FIG. 2, the liquid crystal driving ICs 13a, 13b, 1 are connected through a wiring cable 27 in accordance with an instruction from an external device, for example, an electronic device such as a portable telephone.
3c to activate the first electrode 17a or the second electrode 17b.
(See FIG. 3). A scanning voltage is applied to each one of the rows, and a data voltage based on a display image is applied to the other of the electrodes for each pixel. The light passing through each of the selected pixel portions is modulated, and an image such as a character or a number is displayed on the liquid crystal display surface side of the liquid crystal panel 4.

As can be understood from the above description made with reference to FIG. 3, in the present embodiment, the first wiring board 8 and the second wiring board 9 are connected to the same surface of the third wiring board 10. Instead, they are connected separately on the front and back surfaces of the third wiring board 10. Therefore, the first wiring board 8 and the second wiring board 9
Each of the third wiring boards 1 is not disturbed by the other.
It can be formed widely over a wide range within the zero area range.
For this reason, the area of the first wiring substrate 8 and the second wiring substrate 9 can be increased without increasing the area of the pair of substrates 7a and 7b constituting the liquid crystal panel 4, and as a result, the liquid crystal driving IC 13a It is possible to mount a number of IC chips such as 13c and other chip components used as necessary on the first wiring board 8 and the second wiring board 9.

In this case, even if the number of chip components increases, the area of the pair of substrates 7a and 7b constituting the liquid crystal panel 4 does not increase, so that the display contributes to the plane area of the pair of substrates 7a and 7b. It is possible to prevent the useless area from being generated.

Further, in the present embodiment, a plurality of liquid crystal driving ICs 13a and 13b are mounted on the first wiring substrate 8, and the IC chips are further moved in the direction toward the pair of substrates 7a and 7b, that is, toward the liquid crystal panel 4. Since they are arranged side by side in the direction toward each other, even when the area of the first wiring board 8 is small, a plurality of IC chips can be mounted on the board without difficulty.

In particular, in the present embodiment, the plurality of liquid crystal driving ICs 13a and 13b are arranged side by side in the direction toward the liquid crystal panel 4 so that their longitudinal directions are substantially parallel to each other. Liquid crystal drive IC
13a and 13b can be more efficiently mounted on a substrate.

Further, in this embodiment, as can be seen from FIGS. 1 and 2, the first wiring board 8 and the second wiring board 9 are arranged in a positional relationship where their portions K overlap with each other when viewed in plan. Further, among the wiring patterns 12 formed on the first wiring board 8, the wiring pattern indicated by reference numeral 12a passes through the region K where the first wiring board 8 and the second wiring board 9 overlap each other as described above. Is patterned as follows. With this configuration, the first wiring board 8
Also, even when the area of the second wiring board 9 is small, the wiring pattern can be efficiently patterned without generating a useless area on those boards.

As described above, according to the liquid crystal device 1 of the present embodiment, even if the area of the first wiring board 8 is formed small, a plurality of liquid crystal driving ICs 13 are provided on the first wiring board 8.
a and 13b can be provided without difficulty, and as a result, the number of output lines of the IC can be increased. Therefore, a high-definition image can be displayed on the liquid crystal display surface of the liquid crystal panel 4 without unnecessarily increasing the area of the liquid crystal panel 4, and R (red), G (green), and B (blue) The color display requiring three electrodes can also be performed without difficulty without unnecessarily increasing the area of the liquid crystal panel 4.

According to the board connection structure 15 shown in FIG. 4, the connection terminals 24b and 24c of the first wiring board 8 are formed in an internal region other than the side edge of the first wiring board 8,
Further, the connection terminals 26b and 26c of the third wiring board 10 are formed in an internal region which is not an edge of the third wiring board 10, and the connection terminals 24b, 24c and 26b, 2
6c, the first and second wiring boards 8 and 10 are overlapped with each other and connected to each other.
0 for connecting electrically with 0.
Even when the number of terminals b, 24c and 26a, 26b, 26c increases, it is not necessary to increase the width of the side edges of the substrates 8 and 10, so that the substrates 8 and 1
0 can be kept small.

Further, in the board connection structure 15 shown in FIG. 4, a plurality of liquid crystal driving ICs 13a and 13b are mounted on the first wiring board 8 which is a flexible board, and the liquid crystal driving ICs 13a and 13b are mounted. The connection terminals 24b and 24c connected to at least one of them are connected to their liquid crystal drive I
It was arranged at an intermediate position between C13a and 13b. Also, a plurality of openings 28 for accommodating the plurality of liquid crystal driving ICs 13a and 13b are formed in the third wiring substrate 10 which is a non-flexible substrate, and connection terminals are provided at intermediate positions between the openings 28. 26 and 26c were formed.

Further, the liquid crystal driving I on the first wiring substrate 8
C13a and 13b are the openings 28 on the third wiring board 10
The substrates 8 and 10 are superimposed on each other so as to be accommodated in the connection terminals 24b and 24c.
And the connection terminals 26b and 26c were connected to each other by soldering or the like. By employing the above-described substrate connection structure, the substrate structure including the plurality of liquid crystal driving ICs 13a and 13b and the circuits associated therewith can be formed very small.

(Other Embodiments) The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications may be made within the scope of the invention described in the claims. Can be modified.

For example, in the embodiment shown in FIG. 1, a liquid crystal device is exemplified as an electro-optical device. However, other electro-optical devices, for example, an optical device using an electroluminescence (EL) element as an electro-optical material, a plasma device, or the like. The present invention can be applied to various electro-optical devices such as a display (PDP) and an optical device using a field emission device (FED) as an electro-optical material.

In the embodiment shown in FIG. 1, the light guide 3
Although the liquid crystal device 1 has a structure using the light guide 3, the present invention can be applied to a liquid crystal device having a structure in which a light reflection plate is mounted on the back side of the liquid crystal panel 4 without using the light guide 3.

In the substrate connection structure 15 shown in FIG.
Although the case where two IC chips, that is, the liquid crystal driving ICs 13a and 13b are mounted on the first wiring board 8, has been exemplified, the number of IC chips is not limited to a specific number. Also,
The present invention includes a case where other chip components such as a resistor and a capacitor are provided instead of or in addition to the IC chip.

In the substrate connection structure 15 shown in FIG.
Although the case where the first wiring board 8 which is a flexible board and the third wiring board 10 which is a non-flexible board are connected has been exemplified, the connection target may be between flexible boards, or Non-flexible substrates may be used.

[0060]

According to the substrate connection structure of the present invention, the formation positions of the connection terminals for connecting a pair of substrates are formed in the internal regions without being limited to the side edges of each substrate. Therefore, even when the number of connection terminals increases due to an increase in the number of terminals of IC chips and the like mounted on the pair of substrates, the width dimension of the side edge of those substrates is increased. Therefore, the planar shape of the pair of substrates connected to each other can be kept small.

Further, according to the electro-optical device of the present invention, the planar shape of the pair of substrates constituting the substrate connection structure included therein can be kept small, so that the planar shape of the entire electro-optical device can be kept small.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an embodiment of a liquid crystal device which is an example of an electro-optical device according to the invention.

FIG. 2 is a perspective view showing an external shape of a back side of the liquid crystal device of FIG.

FIG. 3 is an exploded perspective view showing the liquid crystal device of FIG. 1 and showing one embodiment of a substrate connection structure according to the present invention.

4 is a perspective view showing the substrate connection structure of FIG. 3 in a further exploded manner.

FIG. 5 is a cross-sectional view illustrating a cross-sectional structure of the liquid crystal device according to line VV in FIG.

FIG. 6 is an exploded perspective view showing an example of a conventional substrate connection structure and an example of a conventional liquid crystal device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Liquid crystal device 2 LED 3 Light guide 4 Liquid crystal panel 6 Adhesive 7a, 7b Substrate (panel board) 8 1st wiring board 9 2nd wiring board 10 3rd wiring board 11 Base layer 12 Wiring pattern 12a Wiring which passes through an overlapping area. Pattern 13a, 13b, 13c Liquid crystal driving IC (IC chip) 14 Sealing material 14a Liquid crystal injection port 15 Substrate connection structure 16a, 16b Substrate material 17a, 17b Electrode 23 Liquid crystal 24a, 24b, 24c, 24d Connection terminal 26a, 26b, 26c, 26d Connection terminal 27 Wiring cable 28 Opening K Overlap area of wiring board

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2H092 GA05 GA44 GA48 GA50 GA51 HA04 HA25 NA25 PA02 PA08 PA11 PA13 5E344 AA01 AA11 AA21 BB02 BB03 BB04 BB06 CC03 CD04 CD09 CD14 DD02 DD06 EE12 5G435 AA18 BB01 BB05 BBEEBB12

Claims (6)

[Claims] 1. A substrate connection structure in which a pair of substrates each having a connection terminal are connected to each other via the connection terminals, wherein the connection terminals formed on the pair of substrates are respectively A substrate connection structure formed in an internal region other than a side edge portion of the substrate, wherein the pair of substrates are connected to each other by connecting these connection terminals to each other. 2. The substrate connection structure according to claim 1, wherein one of the pair of substrates is a flexible substrate, and the other of the pair of substrates is a non-flexible substrate. 3. The substrate according to claim 2, wherein an IC chip is mounted on the flexible substrate, and connection terminals connected to the IC chip are formed in an internal region of the flexible substrate. Connection structure. 4. The flexible substrate according to claim 3, wherein a plurality of IC chips are mounted on the flexible substrate, and connection terminals connected to the IC chips are arranged at intermediate positions between the IC chips. A plurality of openings for accommodating the plurality of IC chips are formed in the flexible substrate, connection terminals are formed at intermediate positions between the openings, and the flexible substrate and the non-flexible substrate are The substrate connection structure, wherein the IC chips are stacked on each other in a state housed in the opening, and the connection terminals are connected to each other. 5. At least one panel substrate for supporting an electro-optical material, a substrate connected to the panel substrate, and another substrate connected to the substrate, wherein the pair of substrates are provided respectively. In the electro-optical device connected to each other via the connection terminals provided, the connection terminals formed on the pair of substrates are respectively formed in internal regions other than the side edges of the substrates, and these connection terminals are formed. Are connected to each other, whereby the pair of substrates are connected to each other in an overlapping manner. 6. The electro-optical device according to claim 5, wherein the electro-optical material is a liquid crystal, and the panel substrate is a pair of substrates for sealing and supporting the liquid crystal.