JP2002084053A - Electronics - Google Patents

Abstract

(57) [Summary] To provide an electronic device capable of satisfactorily making electrical connection between terminals between an electro-optical panel and a circuit board which are arranged in an overlapped manner. SOLUTION: In a mobile phone, a liquid crystal panel 400 is provided.
When the terminals are electrically connected between the circuit board 7 and the circuit board 7, the connector 65 is mounted on the second flexible board side terminal 609 of the flexible board 60, and then the first flexible board side terminal 608 of the flexible board 60 is mounted. Is electrically connected to the panel-side input / output terminal 481 of the liquid crystal panel 400 by an anisotropic conductive film. Next, the flexible substrate 60 is folded back to the back side, and the second connector electrode 65
The connector 65 is held between the liquid crystal 400 and the circuit board 7 while the connector 9 is pressed against the circuit board-side input / output terminal 781 of the circuit board 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic equipment. More specifically, the present invention relates to an electrical connection technique between an electro-optical panel and a circuit board, which are arranged one above another at a predetermined interval in an electronic device.

[0002]

2. Description of the Related Art Among various electronic devices, portable telephones are:
For example, as shown in FIG. 2, a lower case 6, a circuit board 7 on which various electric circuits for operating the mobile phone 1 are formed, a lighting device 10, a light diffusion sheet 8, and various displays as an electro-optical panel. And the upper case 9 are stacked in this order.
The lighting device 10 includes a light source 11 composed of an LED or the like, a light guide plate 12, a first reflector 15, and a sheet-like second reflector 17.

In this illuminating device 10, a display area 121 in which a liquid crystal panel 400 is arranged is formed as a rectangular recess in the light guide plate 12, and in the display area 121, a corner portion on the distal end side of a bottom wall 124 is formed. , Liquid crystal panel 40
A rectangular through hole 125 for electrically connecting the circuit board 7 to the circuit board 7 is formed. The first reflector 15 includes three side walls 151, 152 surrounding three outer peripheral end surfaces of the light guide plate 12, excluding the side where the keypad region 122 is located, among the four circumferences of the rectangular display region 121 of the light guide plate 12. 153
And a bottom wall portion 154 overlapped on the lower surface of the display area 121
The bottom wall portion 154 also has the light guide plate 12
A rectangular through hole 155 is formed at a position overlapping with the through hole 125.

Accordingly, as shown in FIG. 8, when the first reflector 15, the light guide plate 12, and the liquid crystal panel 400 are stacked on the upper surface side of the circuit board 7, the circuit board 7 and the liquid crystal panel 40 are stacked.
Although the first reflector 15 and the light guide plate 12 are interposed between the liquid crystal panel 0 and the circuit board 7, the circuit board 7 and the liquid crystal panel 400 face each other through the through holes 125 and 155. Therefore, if the rubber connector 79 is sandwiched between the circuit board 7 and the liquid crystal panel 400, the first connector electrode of the rubber connector 79 is pressed against the input / output terminal of the liquid crystal panel 400, while
Since the second connector electrode of the rubber connector 79 is pressed into contact with the circuit board-side input / output terminals of the circuit board 7, the input / output terminals can be electrically connected between the liquid crystal panel 400 and the circuit board 7. .

[0005]

However, in the conventional portable telephone, the input / output terminals of the circuit board 7 are gold-plated on the surface. Although the contact resistance is small only by being pressed, the change in resistance over time does not matter, but the input / output terminals of the liquid crystal panel 400 are formed with the help of the manufacturing process. It is made of an ITO film or the like in the same manner as the electrode pattern for use. For this reason, the electrical connection between the input / output terminal of the liquid crystal panel 400 and the electrode of the rubber connector 79 has a problem that the contact resistance is large only by pressing, and the resistance increases with time. is there. Such a problem of the contact resistance causes a problem that when the display is performed on the liquid crystal panel 400, the non-lighting or the display becomes thin.

[0006] In view of the above problems, an object of the present invention is to provide:
It is an object of the present invention to provide an electronic device capable of satisfactorily making electrical connection between terminals between an electro-optical panel and a circuit board which are arranged in an overlapping manner.

[0007]

According to the present invention, there is provided an electro-optical panel comprising: an electro-optical panel; and a circuit board which is overlapped with the electro-optical panel at a predetermined interval. In an electronic device in which a panel-side input / output terminal and a circuit board-side input / output terminal are formed on a surface on a side where an optical panel and the circuit board face each other, the panel-side input / output terminal is provided on a surface side of the flexible substrate. The formed first flexible board side terminal is electrically connected to the first flexible board side terminal by a conductive material, and the surface of the flexible board has the first side on the side of the surface of the flexible board.
A first connector electrode soldered to a second flexible board side terminal electrically connected to the flexible board side terminal at a predetermined distance from the first flexible board side terminal; A connector with a second connector electrode for electrical connection is mounted,
The flexible board is folded so that the second connector electrode overlaps the circuit board side input / output terminal,
The connector is characterized in that the second connector electrode is sandwiched between the electro-optical panel and the circuit board such that the second connector electrode is pressed against the circuit board-side input / output terminal.

In the specification of the present application, an input / output terminal means a terminal for inputting or outputting a signal or power, and is not limited to a terminal for performing both input and output.

In the present invention, the second connector electrode and the circuit board side input / output terminal are preferably plated with gold on the surface.

In the present invention, the panel-side input / output terminals are formed of, for example, an ITO film.

In the present invention, the panel-side input / output terminals are:
Instead of pressing against the first flexible board side terminal,
Since the panel-side input / output terminals are made of an ITO film because they are electrically connected by a conductive material such as an anisotropic conductive film, the electric connection portion has low contact resistance and The change in resistance over time does not matter.
Further, the second connector electrode of the connector mounted on the flexible board is elastically pressed against the input / output terminal on the circuit board side. Since the output terminal is usually plated with gold or the like, the electrical connection portion has a small contact resistance even if it is pressed, and its resistance change with time does not matter. Therefore, when displaying on the electro-optical panel, it is possible to avoid problems such as non-lighting and a thin display due to an increase in resistance of an electrical connection portion.

In the present invention, the electro-optical panel includes:
For example, a liquid crystal panel.

In the present invention, the conductive material is, for example,
It is an anisotropic conductive film.

In the present invention, for example, at least a light guide plate for guiding light from a light source to the electro-optical panel may be disposed between the circuit board and the electro-optical panel. By arranging such a light guide plate, a gap is formed between the electro-optical panel and the circuit board, but even with such a gap, according to the present invention,
The input / output terminals can be reliably electrically connected between the electro-optical panel and the circuit board.

[0015]

Embodiments of the present invention will be described with reference to the accompanying drawings.

(Overall Configuration of Electronic Equipment) FIG. 1 is a perspective view showing the appearance of a mobile phone as an example of the electronic equipment to which the present invention is applied, and FIG. 2 is an exploded view showing the configuration of the main part of this mobile phone. It is a perspective view. FIG. 3 shows the structure of this mobile phone.
It is a longitudinal cross-sectional view which shows the state which laminated | stacked the circuit board, the 1st reflective material, the 2nd reflective material, the light guide plate, the light-diffusion sheet, and the liquid crystal panel. Note that the basic configuration of the electronic apparatus according to the present embodiment is common to that of the related art, and therefore, the common parts will be described with the same reference numerals.

In FIG. 1, a portable telephone 1 of the present embodiment has a display unit 2 using a liquid crystal panel 400 as an electro-optical panel in an upper half thereof, and a plurality of key buttons in a lower half thereof. The operation unit 3 in which the 101 is arranged is configured. A speaker hole 4 is formed above the display unit 2, and a microphone hole 5 is formed below the operation unit 3.

As shown in FIG. 2, the portable telephone 1 has a lower case 6, a circuit board 7 on which various electric circuits for operating the portable telephone 1 are formed, a lighting device 10, a light diffusion sheet 8, an electric A liquid crystal panel 400 for performing various displays as an optical panel and an upper case 9 are stacked in this order. In FIG. 2, illustration of a speaker or a microphone is omitted.

The lighting device 10 includes a light source 11 composed of an LED or the like, and a light guide plate 1 composed of a transparent plastic molded product.
2. First reflector 1 made of plastic molded product
5 and a sheet-like second reflector 17.

In the lighting device 10, the light guide plate 12 includes:
A display area 121 in which the liquid crystal panel 400 is arranged is formed as a rectangular recess, and a keypad area 122 in which a plurality of key buttons 101 are arranged is formed in an area adjacent to the display area 121. Light guide plate 12
Are formed at two places at the tip of the light emitting device, each of which has a light source 11 made of an LED or the like.

In the display area 121 of the light guide plate 12, the bottom wall 1
A rectangular through-hole 125 for electrically connecting the liquid crystal panel 400 and the circuit board 7 is formed in a corner portion on the front end side of 24.

The first reflector 15 surrounds three outer peripheral end faces of the light guide plate 12 excluding the side where the keypad area 122 is located, of the four circumferences of the rectangular display area 121 of the light guide plate 12.
One side wall portion 151, 152, 153 and the display area 12
1 and a bottom wall portion 154 that is superimposed on the lower surface of the first member.
A through hole 159 is formed in the bottom wall portion 154 of the first reflecting member 15 at a position overlapping with the concave portion 123 of the light guide plate 12. This through hole 159 is provided in the circuit board 7 with the first reflecting material 1.
5 is a hole for passing the light source 11 mounted on the circuit board 7 through the recess 123 of the light guide plate 12 when the light guide plate 5 and the light guide plate 12 are overlapped.

The bottom wall portion 154 of the first reflector 15
, A rectangular through hole 155 is also formed at a position overlapping the through hole 125 of the light guide plate 12.

Therefore, as shown in FIG. 3, when the first reflector 15, the light guide plate 12, and the liquid crystal panel 400 are stacked on the upper surface side of the circuit board 7, the circuit board 7 and the liquid crystal panel 40
Although the first reflector 15 and the light guide plate 12 are interposed between the liquid crystal panel 0 and the circuit board 7, the circuit board 7 and the liquid crystal panel 400 face each other through the through holes 125 and 155. Therefore, as described later, the circuit board 7 is provided through the through holes 125 and 155.
The input / output terminals can be electrically connected to each other at the portion where the liquid crystal panel 400 and the liquid crystal panel 400 face each other.

The operation unit 3 of the upper case 9 and the light guide plate 12
Button holes 90, 120, and 170 in which the translucent key buttons 101 are arranged are formed at positions overlapping each other in the keypad region 122 and the sheet-like second reflector 17. Button holes 90, 120, 1
Each of the key buttons 101 is arranged inside 70.

(Configuration of Liquid Crystal Panel 400) The configuration of the liquid crystal panel 400 used as the electro-optical panel in the mobile phone 1 of the present embodiment will be described with reference to FIGS.

FIGS. 4 and 5 show the liquid crystal panel 4 respectively.
00 is a perspective view and an exploded perspective view of 00.

Referring to FIG. 4 and FIG.
Numeral 0 denotes a passive matrix type color liquid crystal panel, in which a liquid crystal enclosing region 435 is partitioned by a sealing material 430 between a pair of transparent substrates made of rectangular glass or the like bonded by a sealing material 430 via a predetermined gap. In addition, liquid crystal is sealed in the liquid crystal sealing region 435. Here, of the pair of transparent substrates,
The substrate on which the plurality of rows of first electrode patterns 440 extending in the vertical direction in the liquid crystal sealing area 435 are formed is referred to as a first transparent substrate 410, and the plurality of rows of the plurality of rows extending in the horizontal direction within the liquid crystal sealing area 435 The substrate on which the second electrode pattern 450 is formed is referred to as a second transparent substrate 420.

The liquid crystal panel 400 shown here is of a transmissive type, and performs a predetermined display using the illumination device 10 shown in FIG. 2 as a backlight. Therefore, a polarizing plate 461 is attached to the outer surface of the second transparent substrate 420, and the first transparent substrate 41
A polarizing plate 462 is attached to the outer surface of the zero. In addition,
On the second transparent substrate 420, a first electrode pattern 440 is provided.
Red (R), green (G), and blue (B) color filters (not shown) are formed in a region corresponding to the intersection of the color filter and the second electrode pattern 450. An insulating flattening film, a second electrode pattern 450,
And an alignment film are formed in this order. On the other hand, the first transparent substrate 410 has the first electrode pattern 4
40 and an alignment film are formed in this order. In the liquid crystal panel 400, both the first electrode pattern 440 and the second electrode pattern 450 are made of an ITO film (I
ndium Tin Oxide / transparent conductive film).

In the liquid crystal panel 400, each of the first transparent substrate 410 and the second transparent substrate 420 located in the same direction is used for both inputting and outputting signals to the outside and conduction between the substrates. A first terminal formation region 411 and a second terminal formation region 421 formed on each of the first transparent substrate 410 and the second transparent substrate 420 near the substrate sides 418 and 428 are used. Therefore, the second
As the transparent substrate 420, a substrate larger than the first transparent substrate 410 is used, and the first transparent substrate 410 and the second
A driving IC 490 is COG mounted on a portion 425 of the first transparent substrate 410 where the second transparent substrate 420 extends from the substrate side 418 when the transparent substrate 420 is bonded.

Further, the second terminal formation region 421 of the second transparent substrate 420 is closer to the substrate side 421 than the driver IC 490.
A panel-side input / output terminal 481 is formed in a portion located on the side of.

On the other hand, the second terminal formation region 421
Since the portion located on the liquid crystal enclosing region 435 side of the driving IC 490 is used for inter-substrate conduction with the first transparent substrate 410 side, it is formed in the overlapping portion with the first transparent substrate 410. ing. Further, in the first transparent substrate 410, the first terminal formation region 411 is used for inter-substrate conduction with the second transparent substrate 420 side.
The second transparent substrate 420 is formed at an overlapping portion with the second transparent substrate 420.

Accordingly, the first transparent substrate 410 and the second transparent substrate 420 are connected to each other by the sealing material 43 containing the inter-substrate conducting agent.
0, and the terminals for inter-substrate conduction are conducted between the substrates, and a signal is input from the input / output terminal 481 of the second transparent substrate 420 to the driving IC 490.
Is supplied to the first electrode pattern 440 and the second electrode pattern 450, so that each of the pixels corresponding to the intersection of the first electrode pattern 440 and the second electrode pattern 450 is driven. be able to.

Here, the panel-side input / output terminals 481 formed on the second transparent substrate 420 are made of an ITO film formed simultaneously with the second electrode pattern 450. In addition, the inter-substrate conduction terminals formed on the first transparent substrate 410 and the second transparent substrate 420 are also formed of the ITO film formed simultaneously with the first electrode pattern 44 and the second electrode pattern 450.

(Electrical connection structure between liquid crystal panel 400 and circuit board 7) The liquid crystal panel 400 thus configured
As shown in FIG. 3, the panel-side input / output terminals 481 of the second transparent substrate 420
5 and 155 are arranged to face each other. In this state, the circuit board-side input / output terminal 781 of the circuit board 7 faces the panel-side input / output terminal 481. The circuit board side input / output terminal 781 has a surface plated with gold.

In electrically connecting the panel-side input / output terminal 481 and the panel-side input / output terminal 781 in such a state, in this embodiment, the connector and the flexible substrate shown in FIG. As shown in (1), the input / output terminals are electrically connected.

FIG. 6 is an explanatory view schematically showing a connector and a flexible board used for electrically connecting the input / output terminals 481 and 781 between the liquid crystal panel 400 and the circuit board 7. FIGS. 7A to 7C are enlarged explanatory diagrams showing a configuration for electrically connecting the input / output terminals 481 and 781 between the liquid crystal panel 400 and the circuit board 7 in the state shown in FIG. is there.

As shown in FIG. 6, in the flexible substrate 60 used in this embodiment, an anisotropic conductive film (ACF) as a conductive material is provided on the panel-side input / output terminals 481 on the front surface or the back surface. A first flexible board side terminal 608 to be electrically connected to the first flexible board side terminal 608, and a second flexible board for connector mounting electrically connected to the first flexible board side terminal 608 at a predetermined distance from the first flexible board side terminal 608. A board-side terminal 609 and a dummy terminal 607 for mounting a connector are formed.

On the other hand, in the connector 65, the second flexible board side terminal 609 of the flexible board 60 is provided.
A first connector electrode 658 to be soldered to the dummy terminal 607 protrudes from both side surfaces, and a second connector electrode for electrically connecting to the circuit board side input / output terminal 781 is provided on the upper surface thereof. 659 are formed. In the connector 65, the first connector electrode 658
The second connector electrode 659 is electrically connected to the second connector electrode 659 in the connector 65 on a one-to-one basis. Further, the second connector electrode 659 is formed in a spring shape, and elastically connects to the circuit board side input / output terminal 781 as described later.

In this embodiment, the first connector electrode 65
The surface of each of the eighth and second connector electrodes 659 is plated with gold.

The flexible substrate 60 thus configured
To electrically connect the input / output terminals 481 and 781 between the liquid crystal panel 400 and the circuit board 7 using the connector 65, first, as shown in FIG. 2 flexible substrate side terminal 609
And the first terminal of the connector 65 with respect to the dummy terminal 607.
After the connector electrode 658 is soldered and the connector 65 is mounted on the flexible board 60, the first flexible board side terminal 608 of the flexible board 60 is connected to the panel side input / output terminal 481 of the liquid crystal panel 400. (Not shown) for electrical connection. Alternatively, the first flexible board side terminal 6 of the flexible board 60
08 is electrically connected to the panel-side input / output terminal 481 of the liquid crystal panel 400 via an anisotropic conductive film, and then the second terminal 609 of the flexible substrate 60 and the dummy terminal 607 are connected to the second terminal 609 of the connector 65. One connector electrode 658 is soldered, and the connector 65 is mounted on the flexible board 60.

Next, as shown in FIG. 7 (B), the flexible substrate 60 is folded back. As a result, the second connector electrode 659 of the connector 65 faces downward. The folded state of the flexible substrate 60 is maintained using an adhesive, a double-sided tape, or the like.

Next, as shown in FIG. 7C, as shown in FIG. 3, the first reflecting material 15
The liquid crystal panel 400 is pressed against the circuit board 7 with the light guide plate 12 and the liquid crystal panel 400 superposed. as a result,
The second connector electrode 659 of the connector 65 is connected to the circuit board 7.
The connector 65 is sandwiched between the liquid crystal 400 and the circuit board 7 in a state of being pressed against the circuit board side input / output terminal 781. Therefore, the panel-side input / output terminal 4 of the liquid crystal panel 400
81 and the circuit board side input / output terminal 781 of the circuit board 7
They are electrically connected via the flexible board 60 and the connector 65.

(Effect of this Embodiment) As described above, in the mobile phone 1 of this embodiment, the panel-side input / output terminal 481 is connected to the first flexible board-side terminal 608 of the flexible board 60.
Is electrically connected to the panel-side input / output terminal 4 by a conductive material such as an anisotropic conductive film instead of by pressure contact.
Even when 81 is formed of an ITO film, this electrical connection portion has a small contact resistance and its resistance change with time does not matter. Further, the second connector electrode 659 of the connector 65 mounted on the flexible board 60 is elastically pressed against the circuit board side input / output terminal 781. And the input / output terminal 781 on the circuit board side are usually plated with gold, so that the electrical connection portion has a small contact resistance even if it is simply pressed, and its resistance changes with time. No problem. Therefore,
When display is performed on the liquid crystal panel 400, problems such as non-lighting and thin display due to an increase in resistance of an electrical connection portion can be avoided.

[Other Embodiments] In each of the above embodiments, an example in which the present invention is applied to the mobile phone 1 has been described. However, the present invention is applied to electronic devices such as other display devices. You may.

In this embodiment, an example using the liquid crystal panel 400 as the electro-optical panel has been described. However, the electro-optical panel is not limited to the liquid crystal panel 400, and an organic electroluminescence type electro-optical panel is used. The present invention may be applied to an electronic device.

[0047]

As described above, in the electronic device according to the present invention, the panel-side input / output terminals are not pressed against the first flexible substrate-side terminals but are made of a conductive material such as an anisotropic conductive agent. Even when the panel-side input / output terminals are made of an ITO film because of the electrical connection, the electrical connection portion has a small contact resistance and its resistance change with time does not matter. . Further, the second connector electrode of the connector mounted on the flexible board is elastically pressed against the input / output terminal on the circuit board side. Since the output terminal is usually plated with gold or the like, the electrical connection portion has a small contact resistance even if it is pressed, and its resistance change with time does not matter. Therefore, when displaying on the electro-optical panel, it is possible to avoid problems such as non-lighting and a thin display due to an increase in resistance of an electrical connection portion.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a mobile phone as an example of an electronic apparatus to which the present invention is applied.

FIG. 2 is an exploded perspective view showing a configuration of a main part of the mobile phone shown in FIG.

FIG. 3 is a longitudinal sectional view showing a state in which a circuit board, a first reflector, a second reflector, a light guide plate, a light diffusion sheet, and a liquid crystal panel are stacked in a mobile phone to which the present invention is applied.

FIG. 4 is a perspective view of a liquid crystal panel used in the mobile phone shown in FIG.

5 is an exploded perspective view of the liquid crystal panel shown in FIG.

FIG. 6 is an explanatory diagram schematically showing a connector and a flexible board used for electrically connecting input / output terminals between a liquid crystal panel and a circuit board in a mobile phone to which the present invention is applied.

FIGS. 7A to 7C are enlarged explanatory views showing a configuration in which input / output terminals are electrically connected between a liquid crystal panel and a circuit board in a mobile phone to which the present invention is applied. is there.

FIG. 8 is a longitudinal sectional view showing a state in which a circuit board, a first reflector, a second reflector, a light guide plate, a light diffusion sheet, and a liquid crystal panel are stacked in a conventional mobile phone.

[Explanation of symbols]

 Reference Signs List 1 mobile phone 2 display unit 3 operation unit 4 speaker hole 5 microphone hole 6 lower case 7 circuit board 8 light diffusion sheet 9 upper case 10 lighting device 11 light source 12 light guide plate 15 first reflecting material 17 second reflecting material 60 flexible Substrate 65 Connector 90, 120, 170 Button hole 101 Key button 121 Display area 122 Keypad area 123 Light guide plate recess 124 Light guide plate bottom wall 125 Light guide plate through hole 151, 152, 153 Side wall portion of first reflective material 154 Bottom wall portion of first reflector 155, 159 Through hole of first reflector 400 Liquid crystal panel (electro-optical panel) 410 First transparent substrate 418, 428 Substrate side 411 First terminal formation region 420 Second Transparent substrate 421 Second terminal formation region 425 Part where transparent substrate overhangs 430 Sealant 435 Liquid Enclosure area 440 First electrode pattern 450 Second electrode pattern 461, 462 Polarizer 490 Driving IC 481 Panel-side input / output terminal 608 First flexible substrate-side terminal 609 Second flexible substrate-side terminal 607 Dummy terminal 658 1 connector electrode 659 2nd connector electrode 781 circuit board side input / output terminal

Claims (6)

[Claims] 1. An electro-optical panel, comprising: a circuit board overlapped with the electro-optical panel at a predetermined interval; and a panel provided on a surface on a side where the electro-optical panel and the circuit board face each other. Wherein the panel-side input / output terminal and the circuit board-side input / output terminal are each formed of a conductive material with respect to the first flexible board-side terminal formed on the surface side of the flexible board. A second surface electrically connected to a surface of the flexible substrate at a predetermined distance from the first flexible substrate-side terminal on a side of the surface of the flexible substrate. The first soldered to the flexible board side terminal
A connector provided with a second connector electrode for elastically electrically connecting to the connector electrode and the circuit board side input / output terminal; and the flexible board, wherein the second connector electrode is provided on the circuit board. The connector is sandwiched between the electro-optical panel and the circuit board such that the second connector electrode is pressed against the circuit board-side input / output terminal. Electronic equipment characterized by the above. 2. The device according to claim 1, wherein at least the second connector electrode and the circuit board side input / output terminal are
Electronic equipment characterized in that its surface is plated with gold. 3. The electronic device according to claim 1, wherein the input / output terminal on the panel side is formed of an ITO film. 4. The method according to claim 1, wherein
The electronic device, wherein the electro-optical panel is a liquid crystal panel. 5. The method according to claim 1, wherein
The electronic device, wherein the conductive material is an anisotropic conductive film. 6. The method according to claim 1, wherein
Between the circuit board and the electro-optical panel, at least, a light guide plate for guiding light from a light source to the electro-optical panel is arranged, so that the circuit board and the electro-optical panel are An electronic device, wherein the electronic device faces each other at a predetermined interval.