JP2003330381A - Display device and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device which can effectively suppress the unnecessary radiation to an observer side in spite of simple configuration and facilitates connection to a grounding potential necessary for suppressing the unnecessary radiation. <P>SOLUTION: The liquid crystal display device (1) is provided with conducting layers (21) above a driver IC and peripheral circuit IC (14) and the conducting layers are connected to the grounding potential. The connection to the grounding potential is performed by interposing gaskets (22) between a metallic cabinet (19) of the electronic apparatus having the liquid crystal display device and the conducting layers. Since the conducting layers are thin, the layers hardly bring about an increase of the size and weight. All the segments of the conducting layers can be used for connection to the grounding potential and the occurrence of restriction in the configuration of the electronic apparatus is obviated. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying an image, and more particularly to a display device capable of preventing unnecessary radiation from a circuit.

[0002]

2. Description of the Related Art In recent years, the development of thin display devices has been remarkable, and is widely used in portable electronic devices such as mobile phones and PDAs and personal computers. Thin display devices include liquid crystal display devices and organic EL (electroluminescence) devices.
Although there are display devices and the like, these generally include a display unit for displaying an image, a driver IC for driving the display unit, and a peripheral circuit IC for receiving a signal from the outside and controlling the driver IC.

The structure of a conventional display device is shown in FIGS. 7 and 8 by taking a liquid crystal display device as an example. FIG. 7 shows a liquid crystal display device 8.
8 is a schematic cross-sectional view of FIG. 8 and FIG. 8 is a schematic plan view of a part of the liquid crystal display device 8 and an electronic device including the same. As shown in FIG. 7, the liquid crystal layer 11 for displaying an image is
It is sandwiched between a first substrate 12a and a second substrate 12b made of glass, and polarizing plates 13a and 13b are attached to the lower surface of the first substrate 12a and the upper surface of the second substrate 12b, respectively.

The driver IC and the peripheral circuit IC14 are
It is integrally formed around the liquid crystal layer 11 (driver monolithic), and like the liquid crystal layer 11, the first and second substrates 1 are formed.
It is sandwiched between 2a and 12b. In addition, a configuration (COG) in which the driver IC and the peripheral circuit IC 14 are separately created and bonded on the substrate 12a in a chip state may be adopted.

The liquid crystal display device 8 is illuminated from the polarizing plate 13a side by a backlight light source (not shown). Liquid crystal layer 1
An area above 1 is a display area 15 where an image can be seen, and an area above the driver IC and the peripheral circuit IC 15 is a non-display area 16 where an image cannot be seen.

As shown in FIG. 8, the driver IC and the peripheral circuit IC 14 of the liquid crystal display device 8 are connected to the substrate 18 of the electronic device 9 by the flexible substrate 17. The peripheral circuit IC is connected to the electronic device 9 via the flexible substrate 17.
The driver IC is controlled according to the video signal supplied from the liquid crystal layer 11 to display the video image represented by the video signal. The portion of the driver IC of the liquid crystal display device 8 and the peripheral circuit IC 14 that should be at the ground potential is the flexible substrate 1
It is connected to the ground potential portion of the substrate 18 of the electronic device 9 via 7.

In the liquid crystal display device 8, a driver IC
Also, there is no structure for blocking electromagnetic waves above the peripheral circuit IC14, that is, on the observer side. In addition, the liquid crystal display device 8
Are connected to the ground potential of the electronic device 9 via only the flexible substrate 17. However, an electromagnetic wave is easily generated in the driver IC and the peripheral circuit IC, and it is desirable to suppress the emission of this electromagnetic wave (unnecessary radiation) from the viewpoint of the observer's health. Therefore, a driver IC and a peripheral circuit IC are provided by a metal shield case having a U-shaped cross section.
It has been proposed to suppress unnecessary radiation by covering the side, upper and lower sides of, and connecting the shield case to the ground potential.

[0008]

However, although this structure is useful for suppressing unnecessary radiation, it is not suitable for thinning and weight saving because it uses a metal shield case. Further, since the liquid crystal display device and the shield case are separate bodies, the assembly process becomes complicated.

As another method for suppressing unnecessary radiation, it is conceivable to coat the inner surface of the cabinet of an electronic device with a conductive paint such as electroless nickel plating and extend it above the driver IC and peripheral circuit IC. . But,
In that configuration, the contact to the ground potential is far from the driver IC and the peripheral circuit IC, so that the effect cannot be expected so much.

The present invention has been made in view of the above problems, and it is possible to effectively suppress unnecessary radiation to the observer side even though it has a simple structure, and the ground required for suppressing unnecessary radiation. It is an object to provide a display device which can be easily connected to a potential. It is another object of the present invention to provide a compact and lightweight electronic device equipped with this display device.

[0011]

In order to achieve the above object, according to the present invention, in a display device having a driver IC and a peripheral circuit IC on a substrate provided with a display unit for displaying an image, a driver IC and A conductive layer connected to the ground potential is provided above the peripheral circuit IC.

In this display device, unnecessary radiation upward from the driver IC and the peripheral circuit IC can be blocked by the conductive layer, and when used by the observer to observe from above the display portion, It is possible to prevent the observer from receiving unnecessary radiation. The conductive layer can be formed thin, and the increase in the thickness and weight of the display device can be suppressed only slightly. Further, any part of the conductive layer may be used as the connection part to the ground potential, and the connection to the ground potential is easy.

The conductive layer is a driver IC and a peripheral circuit IC
Can be installed directly on top of. It is also possible to have a structure in which another substrate sandwiching the driver IC and the peripheral circuit IC together with the substrate is interposed between the driver IC and the peripheral circuit IC and the conductive layer. In the latter configuration, the driver IC and the peripheral circuit IC are protected by the substrate existing between the driver IC and the peripheral circuit IC, and the driver IC and the peripheral circuit IC may be damaged when the conductive layer is connected to the ground potential. Is greatly reduced.

A portion of the driver IC and the peripheral circuit IC, which is connected to the ground potential, may be connected to the conductive layer. With this configuration, it is not necessary to separately provide a wiring for connecting the driver IC and the peripheral circuit IC to the ground potential, and only the signal line needs to be connected to the driver IC and the peripheral circuit IC.

According to the present invention, in an electronic device having a display means, any one of the above display devices is provided as the display means, and the conductive layer of the display device is connected to a portion of the electronic device at the ground potential. To do. Although this electronic device is small and lightweight, it can effectively suppress unnecessary radiation. Further, since any part of the conductive layer can be used for connection to the ground potential, connecting the conductive layer to the ground potential causes almost no restriction on the configuration of the device.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings, taking a liquid crystal display device as an example. FIG. 1 shows the configuration of the liquid crystal display device 1 of the first embodiment.
Shown in. FIG. 1 is a schematic sectional view of the liquid crystal display device 1. As shown in FIG. 1, a liquid crystal layer 11 that is a display unit for displaying an image is sandwiched between a first substrate 12a and a second substrate 12b made of glass, and a lower surface of the first substrate 12a and a second substrate 12a are formed. Polarizing plates 13a and 13b are attached to the upper surface of the substrate 12b. The substrates 12a, 12
b is not limited to glass, and may be made of other materials such as plastic and quartz as long as it can transmit light well.

A driver IC and a peripheral circuit IC 14 are provided near the liquid crystal layer 11 so as to surround the liquid crystal layer 11. Driver IC and peripheral circuit I
C14 is integrally formed as a driver monolithic structure, and like the liquid crystal layer 11, the first and second substrates 1 are formed.
It is sandwiched between 2a and 12b. Of the driver IC and the peripheral circuit IC 14, the driver IC drives each pixel of the liquid crystal layer 11, and the peripheral circuit IC controls the driver IC according to a video signal given from the outside.

The liquid crystal display device 1 is illuminated from the polarizing plate 13a side by a backlight light source (not shown). Polarizing plate 1
Reference numeral 3a denotes linearly polarized light from the light source, and polarizing plate 13b selectively transmits either linearly polarized light whose polarization plane has changed while transmitting the liquid crystal layer 11 or linearly polarized light whose polarization plane has not changed. . This provides the viewer with an image. Above the liquid crystal layer 11 is a display area 15 where an image can be seen, and the driver IC and the peripheral circuit I are displayed.
Above the C14 is a non-display area 16 where the image cannot be seen.

FIG. 2 schematically shows the structure of a part of the liquid crystal display device 1 and an electronic device 5 employing the same. As shown in FIG. 2, the driver IC and the peripheral circuit IC 14 of the liquid crystal display device 1 are connected to the substrate 18 of the electronic device 5 by the flexible substrate 17. Here, the electronic device 5 includes the liquid crystal display device 1 as a display unit, and is, for example, a mobile phone, a PDA, a personal computer, or the like. Driver IC and peripheral circuit IC of the liquid crystal display device 1
A signal is given to the electronic device 14 from the electronic device 5 through the flexible substrate 17. In addition, the driver I of the liquid crystal display device 1
The portion of C and the peripheral circuit IC14 that should be at the ground potential is connected to the portion of the ground potential of the substrate 18 of the electronic device 5 via the flexible substrate 17.

The polarizing plate 13b is provided only in a portion facing the liquid crystal layer 11, and is electrically connected to a portion of the upper surface of the substrate 12b adjacent to the polarizing plate 13b, that is, a portion above the driver IC and the peripheral circuit IC14. A layer 21 is provided. The conductive layer 21 is connected to the ground potential, and blocks unnecessary radiation directed upward from the driver IC and the peripheral circuit IC14. The conductive layer 21 is made of gold, silver, copper,
It is made of metal such as aluminum and solder.

The structure for connecting the conductive layer 21 of the liquid crystal display device 1 to the ground potential is schematically shown in the sectional view of FIG. The cabinet 19 of the electronic device 5 is made of, for example, metal, has conductivity, and extends to above the conductive layer 21. The electric potential of the cabinet 19 is the ground electric potential of the electronic device 5,
The ground potential portion of the substrate 18 described above is connected to the cabinet 19 at a portion not shown. A conductive gasket 22 is interposed between the conductive layer 21 and the cabinet 19, whereby the conductive layer 21 is connected to the ground potential.

An example of the gasket 22 is shown in FIG. (A)
Is a rectangular parallelepiped gasket made of a resin having conductivity and elasticity. (B) is a so-called finger gasket which is a metal plate bent in a Z shape so as to have elasticity.

By using the gasket 22 in this manner, it becomes easy to connect the conductive layer 21 to the ground potential, and the conductive layer 21 can be reliably secured even if there is some error in the distance between the conductive layer 21 and the cabinet 19. Can be at ground potential. By inserting the gasket 22 between the conduction layer 21 and the cabinet 19, a downward force is applied to the conduction layer 21, but the force is stopped by the substrate 12b and almost reaches the driver IC and the peripheral circuit IC14. Absent. Therefore, there is no possibility of damaging the driver IC and the peripheral circuit IC14. Further, since the cabinet 19 exists above the conductive layer 12 and unnecessary radiation is doubly blocked by the conductive layer 21 and the cabinet 19, the conductive layer 21 is temporarily squeezed by the force when the gasket 22 is interposed. Even if is damaged, unnecessary radiation is reliably blocked by the cabinet 19.

The gasket 22 may be arranged anywhere on the conductive layer 21. The conductive layer 21 is a driver IC
Further, since it is provided so as to face the entire peripheral circuit IC14, the existence range of the conductive layer 21 is wide, and many parts can be selected for the arrangement of the gasket 22. Therefore, the conductive layer 21 can be connected to the cabinet 19 with almost no restrictions on the configuration of other parts of the electronic device 5. Instead of using the gasket 22, it is possible to connect the conductive layer 21 to the cabinet 19 by another method, for example, a metal wire.

The configuration of the liquid crystal display device 2 of the second embodiment is schematically shown in the sectional view of FIG. The liquid crystal display device 2 has a first
The liquid crystal display device 1 of the above embodiment is modified to be a driver IC.
Also, the portion of the peripheral circuit IC14 having the ground potential is connected to the conductive layer 21. The configuration for displaying an image is the same as that of the liquid crystal display device 1, and thus a duplicate description will be omitted.

A conductive resin 23 is attached to the end surface of the substrate 12b immediately below the conductive layer 21. The conductive layer 21 is not only above the driver IC and the peripheral circuit IC14 but also above.
It is also located above the resin 23 and is in contact with the resin 23.
Further, the substrate 12a on which the driver IC and the peripheral circuit IC14 are formed reaches below the resin 23,
The portions of the driver IC and the peripheral circuit IC14 that are at the ground potential are extended to a portion below the resin 23 on the upper surface of the substrate 12a.

When sandwiching the liquid crystal layer 11, the driver IC and the peripheral circuit IC 14 between the two substrates 12a and 12b, the conductive paste 2 is provided between the resin 23 and the upper surface of the substrate 12a.
4 is given. Therefore, the portions of the driver IC and the peripheral circuit IC 14 that have the ground potential are connected to the conductive layer 21 via the conductive paste 24 and the conductive resin 23. By connecting the conductive layer 21 to the cabinet 19 of the electronic device 5 similarly to the liquid crystal display device 1, the driver IC and the peripheral circuit IC 14 are connected to the ground potential.

In the liquid crystal display device 2 having such a configuration, the driver IC is mounted via the flexible substrate 17 shown in FIG.
It is not necessary to connect the peripheral circuit IC14 to the ground potential. The flexible board 17 only needs to include the signal line, and it is not necessary to connect the ground line of the flexible board 17 to the board 18 of the electronic device 5. Therefore, the configuration of the electronic device 5 is simplified.

The structure of the liquid crystal display device 3 of the third embodiment is schematically shown in the sectional view of FIG. In the liquid crystal display device 3, the driver IC and the peripheral circuit IC 14 are manufactured separately from the liquid crystal layer 11 to the polarizing plates 13a and 13b for display, and bonded (COG) to the substrate 12a in a chip state. The liquid crystal layer 11 is sealed with resin 25. The conductive layer 2 is formed on the driver IC and the peripheral circuit IC14.
1 is directly provided. The conductive layer 21 is a driver IC
Also, it may be provided after the peripheral circuit IC 14 is bonded to the substrate 12a, but if it is provided when the driver IC and the peripheral circuit IC 14 are produced, it is efficient.

In the liquid crystal display device 3, since the substrate 21b does not exist between the driver IC / peripheral circuit IC14 and the conductive layer 21, the liquid crystal display device 1 of the first embodiment has a gasket so that the electronic device When connected to the cabinet, excessive force may be applied to damage the driver IC and the peripheral circuit IC14. Therefore, it is preferable to connect to the ground potential with a metal wire.

In each of the above-described embodiments, the transmissive liquid crystal display device is taken as an example, but the driver IC and the peripheral circuit IC are used.
The present invention including the conductive layer on the observer side can be applied to a reflective liquid crystal display device and further to other display devices such as an organic EL display device having a different display principle. Further, the display device of the present invention can suppress unnecessary radiation with almost no increase in size and weight, and thus is particularly suitable for portable devices such as mobile phones and PDAs, and is suitable for notebook personal computers. It is also suitable for devices in which the display unit is desired to be thin.

[0032]

In a display device having a driver IC and a peripheral circuit IC on a substrate provided with a display section for displaying an image, a ground potential is provided above the driver IC and the peripheral circuit IC as in the present invention. If the conductive layer to be connected is provided, unnecessary radiation can be effectively suppressed even though the structure is simple, small and lightweight. Further, since any part of the conductive layer may be connected to the ground potential, the connection to the ground potential is easy.

Here, the driver IC and the peripheral circuit IC
If another substrate that sandwiches the driver IC and the peripheral circuit IC together with the substrate is interposed between the conductive layer and the conductive layer, the driver IC and the peripheral circuit IC are protected by the substrate, and the conductive layer is set to the ground potential. The risk of damaging the driver IC and the peripheral circuit IC when connecting to the IC is greatly reduced.

If the portion of the driver IC and the peripheral circuit IC that is connected to the ground potential is connected to the conductive layer, the driver IC and the peripheral circuit IC will be described.
It is not necessary to separately provide a wiring for connecting the signal line to the ground potential, and only the signal line needs to be connected to the driver IC and the peripheral circuit IC, resulting in a simpler configuration.

In an electronic device having a display means, if the display device of the present invention is provided as the display means and the conductive layer of the display device is connected to the ground potential portion of the electronic device, unnecessary radiation is effectively provided. In addition to being able to suppress it, it is easy to reduce the size and weight. Moreover, since every part of the conductive layer of the display device can be utilized for connection to the ground potential, the conductive layer can be connected to the ground potential without inviting restrictions on the configuration of the device.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a configuration of a liquid crystal display device according to a first embodiment.

FIG. 2 is a plan view schematically showing the configuration of a part of the liquid crystal display device according to the first embodiment and an electronic apparatus using the same.

FIG. 3 is a cross-sectional view schematically showing a configuration in which the conductive layer of the liquid crystal display device of the first embodiment is connected to the ground potential.

FIG. 4 is a perspective view schematically showing the configuration of a gasket used for connecting the conductive layer of the liquid crystal display device of the first embodiment to the ground potential.

FIG. 5 is a cross-sectional view schematically showing the configuration of the liquid crystal display device of the second embodiment.

FIG. 6 is a sectional view schematically showing a configuration of a liquid crystal display device of a third embodiment.

FIG. 7 is a sectional view schematically showing the configuration of a conventional liquid crystal display device.

FIG. 8 is a plan view schematically showing the configuration of a part of a conventional liquid crystal display device and an electronic device employing the same.

[Explanation of symbols]

1, 2, 3 liquid crystal display device 5 electronic devices 11 Liquid crystal layer 12a, 12b substrate 13a, 13b Polarizing plate 14 Driver IC and peripheral circuit IC 15 display areas 16 hidden area 17 Flexible substrate 18 Electronic device substrates 19 Electronic equipment cabinets 21 Conductive layer 22 Gasket 23 Conductive resin 24 Conductive paste 25 sealing resin

Claims (4)

[Claims] 1. A display device including a driver IC and a peripheral circuit IC on a substrate on which a display unit for displaying an image is provided, and a conductive layer connected to a ground potential is provided above the driver IC and the peripheral circuit IC. A display device comprising. 2. A separate substrate for sandwiching the driver IC and the peripheral circuit IC together with the substrate is interposed between the driver IC and the peripheral circuit IC and the conductive layer.
Display device according to. 3. The display device according to claim 1, wherein portions of the driver IC and the peripheral circuit IC that are connected to the ground potential are connected to the conductive layer. 4. An electronic device comprising display means, wherein the display means is any one of claims 1 to 3.
An electronic device comprising the display device according to the item 1, wherein a conductive layer of the display device is connected to a portion of the electronic device at a ground potential.