Magnetic shielding sheet for digitizer and portable terminal having same

• US 9,578,792 B2
• Filed: 05/27/2014
• Issued: 02/21/2017
• Est. Priority Date: 05/28/2013
• Status: Active Grant

• Current Assignee: Amosense Co., Ltd.
• Original Assignee: Amosense Co., Ltd.
• Inventors: Jang, Kil Jae, Lee, Dong Hoon, Kim, Ki Chul
• Primary Examiner(s): Wilson, Adrian S
• Assistant Examiner(s): Rathod, Abhishek
• Application Number:
  US14/891,797
• Publication Number:
  US 20160106012A1
• Time in Patent Office: 1,001 Days
• US Class Current: 1/1
• CPC Class Codes: B32B 2307/212 Electromagnetic interference shielding
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615
• CPC Class Codes: G06F 1/1656 Details related to functional adaptations of the enclosure, e.g. to provide protection against EMI, shock, water, or to host detachable peripherals like a mouse or removable expansions units like PCMCIA cards, or to provide access to internal components for maintenance or to removable storage supports like CDs or DVDs, or to mechanically mount accessories mounting of accessories to a computer display G06F1/1607; display hoods G06F1/1603; cooling arrangements for portable computers G06F1/203
• CPC Class Codes: G06F 1/203 for portable computers, e.g. for laptops
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/046 by electromagnetic means
• CPC Class Codes: H04B 1/3888 Arrangements for carrying or protecting transceivers
• CPC Class Codes: H05K 9/0083 comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers H05K9/0086 takes precedence
• CPC Class Codes: H05K 9/0086 comprising a single discontinuous metallic layer on an electrically insulating supporting structure, e.g. metal grid, perforated metal foil, film, aggregated flakes, sintering
• CPC Class Codes: H05K 9/0088 comprising a plurality of shielding layers; combining different shielding material structure

Abstract

A magnetic field shielding sheet includes: a magnetic field shielding main sheet disposed on the back of the digitizer to thus prevent affecting the digitizer; and a magnetic field shielding sub-sheet laminated in a dual on at least one of four side edges of the magnetic field shielding main sheet, and to prevent affecting the digitizer by the magnesium frame inside the portable terminal, wherein the magnetic field shielding main sheet includes a shielding layer made of a plurality of pieces, a cover layer adhered to one surface of the shielding layer, and a double-sided tape adhered to the other surface of the shielding layer. A magnetic field arising from various components incorporated in a portable terminal device is shielded by the magnetic field shielding main sheet while the magnetic field shielding sub-sheet prevents a digitizer from being affected by a magnesium frame, thereby enhancing performance of the digitizer.

Claims

1. A magnetic field shielding sheet for a digitizer, the magnetic field shielding sheet comprising:

a magnetic field shielding main sheet that is disposed on a rear surface of the digitizer to thus prevent affecting the digitizer; and

a magnetic field shielding sub-sheet that is laminated in a dual on at least one of four side edges of the magnetic field shielding main sheet, to prevent the digitizer from being affected by a magnesium frame inside a portable terminal device,

wherein the magnetic field shielding main sheet is made of an amorphous alloy or a nanocrystalline alloy, and comprises a shielding layer made of a plurality of pieces by flakes, a cover layer adhered to one surface of the shielding layer, and a double-sided tape adhered to the other surface of the shielding layer, and

wherein the magnetic field shielding sub-sheet is formed of a band shape having a certain width and is attached to a periphery of the magnetic field shielding main sheet while having the same structure as that of the magnetic field shielding main sheet.

2. The magnetic field shielding sheet of claim 1, wherein some parts of the adhesive layer included in the cover layer and the double-sided tape are filled in gaps between the plurality of pieces.

3. The magnetic field shielding sheet of claim 1, wherein the amorphous alloy is a Fe-based amorphous alloy or a Co-based amorphous alloy.

4. The magnetic field shielding sheet of claim 1, wherein thickness of the shielding layer is set to a range of 15˜

35 μ

m, and size of the pieces is set to a range of several tens μ

m˜

3 mm range.

5. The magnetic field shielding sheet of claim 1, further comprising a heat dissipation sheet that is attached on the magnetic field shielding main sheet to dissipate heat generated from components incorporated in the portable terminal device.

6. A portable terminal device comprising:

a case;

a display panel disposed in front of the case;

a digitizer panel disposed on a rear surface of the display panel;

a magnetic field shielding sheet disposed on a rear surface of the digitizer panel;

a magnesium frame mounted inside the case and to which various parts and panels are fixed,

wherein the magnetic field shielding sheet comprises;

a magnetic field shielding main sheet that is placed one a rear surface of the digitizer panel and prevents affecting the digitizer panel; and

a magnetic field shielding sub-sheet that is attached on at least one of four side edges of the magnetic field shielding main sheet, and to prevent affecting the digitizer by the magnesium frame,

wherein the magnetic field shielding main sheet is made of an amorphous alloy or a nanocrystalline alloy, and comprises;

a shielding layer made of a plurality of pieces by a flake-treatment process;

a cover layer adhered to one surface of the shielding layer; and

a double-sided tape adhered to the other surface of the shielding layer, and

wherein the magnetic field shielding sub-sheet is formed of a band shape having a certain width and is attached to a periphery of the magnetic field shielding main sheet while having the same structure as that of the magnetic field shielding main sheet.

7. The portable terminal device of claim 6, wherein some parts of the adhesive layer included in the cover layer and the double-sided tape are filled in gaps between the plurality of pieces.

8. The portable terminal device of claim 6, further comprising a heat dissipation sheet that is attached on the magnetic field shielding main sheet to dissipate heat generated from components incorporated in the portable terminal device.

9. The portable terminal device of claim 6, wherein the magnetic field shielding sub-sheet is provided on a side surface to which the digitizer panel is fixed by the magnesium frame.