US20020024624A1 - Liquid crystal display device - Google Patents

Liquid crystal display device Download PDF

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Publication number
US20020024624A1
US20020024624A1 US09/258,075 US25807599A US2002024624A1 US 20020024624 A1 US20020024624 A1 US 20020024624A1 US 25807599 A US25807599 A US 25807599A US 2002024624 A1 US2002024624 A1 US 2002024624A1
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panel
transparent electrode
lcd
electrode layer
liquid crystal
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US09/258,075
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US6456342B1 (en
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Hidetoshi Takenaka
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Lenovo Innovations Ltd Hong Kong
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NEC Corp
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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/133308—Support structures for LCD panels, e.g. frames or bezels
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133604—Direct backlight with lamps
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/133308—Support structures for LCD panels, e.g. frames or bezels
    • G02F1/133334—Electromagnetic shields
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2202/00—Materials and properties
    • G02F2202/28—Adhesive materials or arrangements

Definitions

  • the present invention relates to a display device and, more particularly, to an improvement in a liquid crystal display device having an electroluminescence (to be referred to as an EL hereinafter) panel as a backlight source.
  • an EL electroluminescence
  • An EL panel is conventionally utilized as a backlight source for a liquid crystal display device.
  • the circuit portions of the display device mounted on the circuit board must be protected from electromagnetic wave noise generated by the EL panel.
  • FIG. 1 In a liquid crystal display device disclosed in Japanese Unexamined Patent Publication No. 9-152605, as shown in FIG. 1, an EL panel 52 is placed on a circuit board 51 by stacking, a liquid crystal panel 54 is placed on an emission surface 52 a side of the EL panel 52 by stacking, and a frame 55 is mounted on the surface of the liquid crystal panel 54 .
  • a shield layer 53 is formed on the lower surface of the EL panel 52 . Since the shield layer 53 is provided between the EL panel 52 and circuit board 51 , the electromagnetic wave noise generated by the EL panel 52 is prevented from adversely affecting the respective circuits on the circuit board 51 .
  • the electromagnetic wave noise generated by the EL panel can be prevented from adversely affecting the respective circuits on the circuit board. If, however, the liquid crystal display device is applied to a portable terminal such as a cellular phone or PHS, since a display 33 is arranged near an ear piece 32 , as shown in FIG. 2, the acoustic noise generated by the EL panel increases due to the resonance of the display 33 . Even slight noise becomes offensive to the ear to discomfort the user.
  • the present invention has been made in consideration of the above situation of the prior art, and has its object to provide a liquid crystal display device in which noise output from a speech reception port and a display due to acoustic noise from an EL panel can be decreased.
  • a liquid crystal display device comprising a shield layer for acoustic noise prevention between an LCD and an EL panel serving as a backlight source for the LCD.
  • the present invention also has auxiliary aspects as follows.
  • the shield layer of the first main aspect is fixed to a surface of the EL panel by adhesion.
  • the shield layer of the first main aspect is fixed to the LCD through a double-coated tape by adhesion.
  • the shield layer of the first main aspect is a transparent electrode layer connected to ground.
  • the transparent electrode layer of the third auxiliary aspect is formed on one entire surface of the EL panel.
  • the transparent electrode layer of the third auxiliary aspect has an impedance set to less than several ten k ⁇ .
  • the shield layer of the first main aspect is a conductor selected from a group consisting of an ITO foil, an aluminum foil and silver foil.
  • a liquid crystal display device comprising a ground plate between an LCD and an EL panel serving as a backlight source for the LCD.
  • the ground plate of the second main aspect is formed by forming a transparent electrode layer on one surface of a PET film.
  • an electromagnetic wave preventive ground plate having a transparent electrode layer or transparent electrode connected to ground is placed between an LCD and an EL panel to shield an electric field that varies in accordance with a drive frequency generated by the EL panel.
  • Resonance acoustic noise
  • the EL panel and the transparent electrode of the LCD can accordingly be decreased.
  • noise output from the ear piece and display can be decreased.
  • FIG. 1 is an exploded perspective view showing the main components of a conventional liquid crystal display device
  • FIG. 2 is a front view showing a conventional cellular phone
  • FIG. 3 is an exploded perspective view showing the main components of a liquid crystal display device according to the present invention.
  • FIG. 4 is a schematic sectional view of an EL panel and an LCD shown in FIG. 3 according to an embodiment.
  • FIG. 5 is a schematic sectional view of a modification of an EL panel and an LCD.
  • FIG. 3 is an exploded perspective view of the main components of a display device according to an embodiment.
  • the display device of this embodiment has a circuit board 23 on which mounting parts are mounted at predetermined positions.
  • the circuit board 23 and the lower surface of an EL panel 1 are adhered to each other through a double-coated tape 22 a .
  • the double-coated tape 22 a is used for fixing the EL panel 1 to the circuit board 23 .
  • vibration of the EL panel 1 can be suppressed.
  • the EL panel 1 is provided with a ground terminal 25 , an upper surface electrode terminal 26 , and a lower surface electrode terminal 27 .
  • a transparent electrode layer (not shown) formed on the upper surface of the EL panel 1 , and an LCD 2 are adhered to each other through a double-coated tape 22 b .
  • the double-coated tape 22 b is employed to fix the LCD 2 and is preferably a thin tape having a thickness of about 0.1 ⁇ m (micrometer).
  • FIG. 4 shows the sectional arrangement of the EL panel 1 and LCD 2 shown in FIG. 3.
  • the EL panel 1 is constituted by a PET film 7 , a transparent electrode layer 8 , an emission layer 9 , an insulator layer 10 , a rear electrode layer 11 , and an insulating layer 12 .
  • the PET film 7 is formed of polyester
  • the transparent electrode layer 8 is formed by forming a thin indium-tin oxide (ITO) film on the surface of the PET film 7 by vapor deposition.
  • the emission layer 9 is formed of ZnS (zinc sulfide) or the like
  • the insulator layer 10 is formed of an insulator such as a rubber-based resin.
  • the rear electrode layer 11 is formed of carbon
  • the insulating layer 12 is formed by overcoating such as resist printing.
  • An acoustic noise preventive shield layer preferably a transparent electrode layer 6 , connected to ground through the ground terminal 25 is formed on the surface of the EL panel 1 .
  • the transparent electrode layer 6 is desirably formed on the surface of the EL panel 1 as large as possible. Hence, it is preferable to form the transparent electrode layer 6 on the surface of a large PET film by vapor deposition and to pattern it into the shape of the EL panel 1 , so that it is present on the entire surface of the EL panel 1 .
  • the impedance of the transparent electrode layer 6 i.e., the resistance, is desirably set to a low value, e.g., less than several ten k ⁇ .
  • a conductor such as an aluminum foil or a silver foil having a low resistance
  • a transparent electrode layer having a high optical transmission such as, for example, an ITO foil is desirably used.
  • An inverter circuit 3 is controlled by a CPU (not shown). For example, when the user operates a switch (not shown), the inverter circuit 3 boosts the voltage of a DC power supply 4 and converts the voltage to an AC signal. The AC signal is applied to the EL panel 1 through the upper surface electrode terminal 26 and lower surface electrode terminal 27 to cause it to emit light.
  • the voltage of the output signal from the inverter circuit 3 is usually as high as AC 100 V, and a drive frequency in an audio frequency band of about 200 Hz to 600 Hz is used.
  • the LCD 2 is constituted by a glass plate 13 having a polarizing film, a transparent electrode layer 14 , a liquid crystal 15 , a transparent electrode layer 16 , and a glass plate 17 having a polarizing film, and is connected to a drive circuit 5 .
  • the present invention has been described so far by way of its preferred embodiment.
  • the liquid crystal display device according to the present invention is not limited to the above embodiment.
  • a ground plate 19 on which a transparent electrode layer 21 formed on one surface of a PET film 20 is formed, may be placed between an LCD 2 and an EL panel 18 , as shown in the modification of FIG. 5.
  • the transparent electrode layer 21 is connected to ground.
  • the ground plate 19 must be fixed by, e.g., adhering it to the EL panel 18 .
  • the transparent electrode layer 21 is formed on the separate PET film 20 by vapor deposition.
  • this liquid crystal display device is inferior to that shown in FIG. 4 in terms of cost, optical transmission, thickness, and assembly easiness, it is excellent as a temporary countermeasure in the manufacturing process.
  • the EL panel is fixed to the circuit board with the double-coated tape.
  • the EL panel may be fixed by adhering it to a rigid substrate (base).

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  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Electroluminescent Light Sources (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Liquid Crystal (AREA)

Abstract

A liquid crystal display device includes a shield layer for acoustic noise prevention between an LCD and an EL panel serving as a backlight source for the LCD. The shield layer is fixed to the surface of the EL panel by adhesion.

Description

    BACKGROUND OF THE INVENTION
  • 1. Field of the Invention [0001]
  • The present invention relates to a display device and, more particularly, to an improvement in a liquid crystal display device having an electroluminescence (to be referred to as an EL hereinafter) panel as a backlight source. [0002]
  • 2. Description of the Prior Art [0003]
  • An EL panel is conventionally utilized as a backlight source for a liquid crystal display device. When an EL panel is used as a backlight source, the circuit portions of the display device mounted on the circuit board must be protected from electromagnetic wave noise generated by the EL panel. [0004]
  • In a liquid crystal display device disclosed in Japanese Unexamined Patent Publication No. 9-152605, as shown in FIG. 1, an [0005] EL panel 52 is placed on a circuit board 51 by stacking, a liquid crystal panel 54 is placed on an emission surface 52 a side of the EL panel 52 by stacking, and a frame 55 is mounted on the surface of the liquid crystal panel 54. A shield layer 53 is formed on the lower surface of the EL panel 52. Since the shield layer 53 is provided between the EL panel 52 and circuit board 51, the electromagnetic wave noise generated by the EL panel 52 is prevented from adversely affecting the respective circuits on the circuit board 51.
  • In the liquid crystal display device of this type, the electromagnetic wave noise generated by the EL panel can be prevented from adversely affecting the respective circuits on the circuit board. If, however, the liquid crystal display device is applied to a portable terminal such as a cellular phone or PHS, since a [0006] display 33 is arranged near an ear piece 32, as shown in FIG. 2, the acoustic noise generated by the EL panel increases due to the resonance of the display 33. Even slight noise becomes offensive to the ear to discomfort the user.
    • SUMMARY OF THE INVENTION
  • The present invention has been made in consideration of the above situation of the prior art, and has its object to provide a liquid crystal display device in which noise output from a speech reception port and a display due to acoustic noise from an EL panel can be decreased. [0007]
  • In order to achieve the above object, according to the first main aspect of the present invention, there is provided a liquid crystal display device comprising a shield layer for acoustic noise prevention between an LCD and an EL panel serving as a backlight source for the LCD. [0008]
  • In addition to the first main aspect, the present invention also has auxiliary aspects as follows. [0009]
  • According to the first auxiliary aspect, the shield layer of the first main aspect is fixed to a surface of the EL panel by adhesion. [0010]
  • According to the second auxiliary aspect, the shield layer of the first main aspect is fixed to the LCD through a double-coated tape by adhesion. [0011]
  • According to the third auxiliary aspect, the shield layer of the first main aspect is a transparent electrode layer connected to ground. [0012]
  • According to the fourth auxiliary aspect, the transparent electrode layer of the third auxiliary aspect is formed on one entire surface of the EL panel. [0013]
  • According to the fifth auxiliary aspect, the transparent electrode layer of the third auxiliary aspect has an impedance set to less than several ten kΩ. [0014]
  • According to the sixth auxiliary aspect, the shield layer of the first main aspect is a conductor selected from a group consisting of an ITO foil, an aluminum foil and silver foil. [0015]
  • In order to achieve the above object, according to the second main aspect of the present invention, there is provided a liquid crystal display device comprising a ground plate between an LCD and an EL panel serving as a backlight source for the LCD. [0016]
  • The ground plate of the second main aspect is formed by forming a transparent electrode layer on one surface of a PET film. [0017]
  • According to the present invention having the aspects described above, an electromagnetic wave preventive ground plate having a transparent electrode layer or transparent electrode connected to ground is placed between an LCD and an EL panel to shield an electric field that varies in accordance with a drive frequency generated by the EL panel. Resonance (acoustic noise) between the EL panel and the transparent electrode of the LCD can accordingly be decreased. As a result, noise output from the ear piece and display can be decreased.[0018]
  • The above and many other objects, features and advantages of the present invention will become manifest to those skilled in the art upon making reference to the following detailed description and accompanying drawings in which preferred embodiments incorporating the principle of the present invention are shown by way of illustrative examples. [0019]
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1 is an exploded perspective view showing the main components of a conventional liquid crystal display device; [0020]
  • FIG. 2 is a front view showing a conventional cellular phone; [0021]
  • FIG. 3 is an exploded perspective view showing the main components of a liquid crystal display device according to the present invention; [0022]
  • FIG. 4 is a schematic sectional view of an EL panel and an LCD shown in FIG. 3 according to an embodiment; and [0023]
  • FIG. 5 is a schematic sectional view of a modification of an EL panel and an LCD.[0024]
    • DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
  • Several preferred embodiments of the present invention will be described with reference to the accompanying drawings. [0025]
  • FIG. 3 is an exploded perspective view of the main components of a display device according to an embodiment. [0026]
  • Referring to FIG. 3, the display device of this embodiment has a [0027] circuit board 23 on which mounting parts are mounted at predetermined positions. The circuit board 23 and the lower surface of an EL panel 1 are adhered to each other through a double-coated tape 22 a. The double-coated tape 22 a is used for fixing the EL panel 1 to the circuit board 23. When the EL panel 1 is firmly fixed to the circuit board 23 with the double-coated tape 22 a, vibration of the EL panel 1 can be suppressed. The EL panel 1 is provided with a ground terminal 25, an upper surface electrode terminal 26, and a lower surface electrode terminal 27. A transparent electrode layer (not shown) formed on the upper surface of the EL panel 1, and an LCD 2 are adhered to each other through a double-coated tape 22 b. The double-coated tape 22 b is employed to fix the LCD 2 and is preferably a thin tape having a thickness of about 0.1 μm (micrometer).
  • FIG. 4 shows the sectional arrangement of the EL panel [0028] 1 and LCD 2 shown in FIG. 3.
  • Referring to FIG. 4, the EL panel [0029] 1 is constituted by a PET film 7, a transparent electrode layer 8, an emission layer 9, an insulator layer 10, a rear electrode layer 11, and an insulating layer 12. The PET film 7 is formed of polyester, and the transparent electrode layer 8 is formed by forming a thin indium-tin oxide (ITO) film on the surface of the PET film 7 by vapor deposition. The emission layer 9 is formed of ZnS (zinc sulfide) or the like, and the insulator layer 10 is formed of an insulator such as a rubber-based resin. The rear electrode layer 11 is formed of carbon, and the insulating layer 12 is formed by overcoating such as resist printing.
  • An acoustic noise preventive shield layer, preferably a transparent electrode layer [0030] 6, connected to ground through the ground terminal 25 is formed on the surface of the EL panel 1. The transparent electrode layer 6 is desirably formed on the surface of the EL panel 1 as large as possible. Hence, it is preferable to form the transparent electrode layer 6 on the surface of a large PET film by vapor deposition and to pattern it into the shape of the EL panel 1, so that it is present on the entire surface of the EL panel 1. The impedance of the transparent electrode layer 6, i.e., the resistance, is desirably set to a low value, e.g., less than several ten kΩ. Although a conductor such as an aluminum foil or a silver foil having a low resistance can be used as the transparent electrode layer 6, it decreases the function of the LE as the backlight. Therefore, a transparent electrode layer having a high optical transmission such as, for example, an ITO foil is desirably used.
  • An [0031] inverter circuit 3 is controlled by a CPU (not shown). For example, when the user operates a switch (not shown), the inverter circuit 3 boosts the voltage of a DC power supply 4 and converts the voltage to an AC signal. The AC signal is applied to the EL panel 1 through the upper surface electrode terminal 26 and lower surface electrode terminal 27 to cause it to emit light. The voltage of the output signal from the inverter circuit 3 is usually as high as AC 100 V, and a drive frequency in an audio frequency band of about 200 Hz to 600 Hz is used.
  • The [0032] LCD 2 is constituted by a glass plate 13 having a polarizing film, a transparent electrode layer 14, a liquid crystal 15, a transparent electrode layer 16, and a glass plate 17 having a polarizing film, and is connected to a drive circuit 5.
  • In this arrangement, in the EL panel [0033] 1, when the output signal from the inverter circuit 3 is applied to the transparent electrode layer 8 and rear electrode layer 11, an electric field moving in the vertical direction (to the upper and lower directions) is generated by the transparent electrode layer 8 and rear electrode layer 11 to cause the emission layer 9 to emit light. Although the electric field generated by the transparent electrode layer 8 of the EL panel 1 is also generated in the direction toward the LCD 2, it is shielded as it is attracted by ground due to the low-impedance transparent electrode layer 6 formed on the surface of the EL panel 1.
  • The present invention has been described so far by way of its preferred embodiment. The liquid crystal display device according to the present invention is not limited to the above embodiment. For example, although the transparent electrode layer [0034] 6 connected to ground is formed on the surface of the EL panel 1 in the liquid crystal display device of the above embodiment, a ground plate 19, on which a transparent electrode layer 21 formed on one surface of a PET film 20 is formed, may be placed between an LCD 2 and an EL panel 18, as shown in the modification of FIG. 5. The transparent electrode layer 21 is connected to ground. The ground plate 19 must be fixed by, e.g., adhering it to the EL panel 18. In the liquid crystal display device of this modification, the transparent electrode layer 21 is formed on the separate PET film 20 by vapor deposition. Although this liquid crystal display device is inferior to that shown in FIG. 4 in terms of cost, optical transmission, thickness, and assembly easiness, it is excellent as a temporary countermeasure in the manufacturing process.
  • In the embodiment and its modification described above, the EL panel is fixed to the circuit board with the double-coated tape. Alternatively, the EL panel may be fixed by adhering it to a rigid substrate (base). [0035]

Claims (9)

What is claimed is:
1. A liquid crystal display device comprising a shield layer for acoustic noise prevention between an LCD and an EL panel serving as a backlight source for said LCD.
2. A device according to claim 1, wherein said shield layer is fixed to a surface of said EL panel by adhesion.
3. A device according to claim 1, wherein said shield layer is fixed to said LCD through a double-coated tape by adhesion.
4. A device according to claim 1, wherein said shield layer is a transparent electrode layer connected to ground.
5. A device according to claim 4, wherein said transparent electrode layer is formed on one entire surface of said EL panel.
6. A device according to claim 4, wherein said transparent electrode layer has an impedance set to less than several ten kΩ.
7. A device according to claim 1, wherein said shield layer is a conductor selected from a group consisting of an ITO foil, an aluminum foil and silver foil.
8. A liquid crystal display device comprising a ground plate between an LCD and an EL panel serving as a backlight source for said LCD.
9. A device according to claim 8, wherein said ground plate is formed by forming a transparent electrode layer on one surface of a PET film.
US09/258,075 1998-02-27 1999-02-26 LCD device having a noise-shield layer directly between LCD and EL panel Expired - Lifetime US6456342B1 (en)

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JP04771498A JP3241657B2 (en) 1998-02-27 1998-02-27 Display device
JP10-047714 1998-02-27
JP047714/1998 1998-02-27

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6680723B2 (en) * 2000-06-09 2004-01-20 Seiko Precision Circuits Inc. Display device
US20060103639A1 (en) * 2004-11-16 2006-05-18 Nec Lcd Technologies, Ltd Display device
US20070075956A1 (en) * 2004-11-04 2007-04-05 Matsushita Electric Industrial Co., Ltd. Mobile terminal apparatus
US20070121021A1 (en) * 2005-11-29 2007-05-31 Kaehler John W Display device with acoustic noise suppression
US20090015562A1 (en) * 2003-11-28 2009-01-15 Sharp Kabushiki Kaisha Display system
US20110051787A1 (en) * 2009-08-28 2011-03-03 Apple Inc. Electronic device instructions provided using radio signals
US20120140434A1 (en) * 2007-03-15 2012-06-07 Au Optronics Corporation Display Panel and a Light Source Used Therein
US9541961B1 (en) 2015-08-25 2017-01-10 Microsoft Technology Licensing, Llc Shielding via display chassis
US11237654B2 (en) * 2019-03-29 2022-02-01 Au Optronics Corporation Touch display and method for controlling the same

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI990330A (en) * 1999-02-17 2000-08-18 Nokia Mobile Phones Ltd Mechanical structure and configuration method of the portable communication device
US7248235B2 (en) * 2001-09-14 2007-07-24 Sharp Kabushiki Kaisha Display, method of manufacturing the same, and method of driving the same
JP4060313B2 (en) * 2004-01-28 2008-03-12 シャープ株式会社 Display device
TWM265641U (en) * 2004-06-09 2005-05-21 Rilite Corportation Double shielded electroluminescent panel
KR100658283B1 (en) * 2005-11-23 2006-12-14 삼성에스디아이 주식회사 A display diode with window assembly and the mobile phone having it

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63173395A (en) 1987-01-13 1988-07-16 三菱化学株式会社 Transparent electromagnetic wave shielding material
JPS6415789A (en) 1987-07-09 1989-01-19 Matsushita Electric Ind Co Ltd Thin film el display panel
JPH02259726A (en) * 1989-03-31 1990-10-22 Toshiba Corp Transparent conductive film, dispersion type el panel and liquid crystal display device
JPH0345985A (en) 1989-07-14 1991-02-27 Hitachi Ltd Liquid crystal display device
JP2855916B2 (en) 1991-10-03 1999-02-10 松下電器産業株式会社 Display device
JPH0745103A (en) * 1993-07-30 1995-02-14 Toshiba Lighting & Technol Corp Lighting system, backlight and liquid crystal display device
GB2290405B (en) 1994-06-11 1998-09-16 Motorola Israel Ltd Rugged liquid crystal display and method of manufacture
JPH08114770A (en) * 1994-08-26 1996-05-07 Omron Corp Optical low-pass filter and dot matrix display device utilizing the same
JP3127774B2 (en) * 1995-03-31 2001-01-29 セイコーエプソン株式会社 Shielding material and liquid crystal display
JPH09152605A (en) 1995-11-30 1997-06-10 Seiko Epson Corp Liquid crystal display device
JP3250173B2 (en) * 1996-07-23 2002-01-28 インターナショナル・ビジネス・マシーンズ・コーポレーション Backlight device for liquid crystal
JP3854392B2 (en) * 1996-11-11 2006-12-06 同和鉱業株式会社 Optical filter
JPH10215085A (en) 1996-11-28 1998-08-11 Casio Comput Co Ltd El noise prevention structure and electronic equipment
JPH10244054A (en) 1997-03-06 1998-09-14 Heiwa Corp Liquid crystal display for pachinko game machine
GB2327288A (en) 1997-07-12 1999-01-20 Motorola Israel Ltd Liquid crystal display assembly

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6680723B2 (en) * 2000-06-09 2004-01-20 Seiko Precision Circuits Inc. Display device
US20090015562A1 (en) * 2003-11-28 2009-01-15 Sharp Kabushiki Kaisha Display system
US7683887B2 (en) 2003-11-28 2010-03-23 Sharp Kabushiki Kaisha Display system
US20070075956A1 (en) * 2004-11-04 2007-04-05 Matsushita Electric Industrial Co., Ltd. Mobile terminal apparatus
US20060103639A1 (en) * 2004-11-16 2006-05-18 Nec Lcd Technologies, Ltd Display device
US20070121021A1 (en) * 2005-11-29 2007-05-31 Kaehler John W Display device with acoustic noise suppression
US8550686B2 (en) * 2007-03-15 2013-10-08 Au Optronics Corporation Display panel and a light source used therein
US20120140434A1 (en) * 2007-03-15 2012-06-07 Au Optronics Corporation Display Panel and a Light Source Used Therein
US20110051787A1 (en) * 2009-08-28 2011-03-03 Apple Inc. Electronic device instructions provided using radio signals
US8761683B2 (en) * 2009-08-28 2014-06-24 Apple Inc. Electronic device instructions provided using radio signals
US9541961B1 (en) 2015-08-25 2017-01-10 Microsoft Technology Licensing, Llc Shielding via display chassis
US10156872B2 (en) 2015-08-25 2018-12-18 Microsoft Technology Licensing, Llc Shielding via display chassis
US11237654B2 (en) * 2019-03-29 2022-02-01 Au Optronics Corporation Touch display and method for controlling the same

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JP3241657B2 (en) 2001-12-25
US6456342B1 (en) 2002-09-24
AU1846199A (en) 1999-09-09
CN1232241A (en) 1999-10-20
GB2334808A (en) 1999-09-01
GB9904542D0 (en) 1999-04-21
JPH11249581A (en) 1999-09-17
AU753656B2 (en) 2002-10-24
GB2334808B (en) 2002-06-05

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