U.S. patent application number 14/198820 was filed with the patent office on 2014-09-18 for digitizer and method of manufacturing the same.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. The applicant listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Joo-Hoon LEE, Sung-Ha PARK.
Application Number | 20140267951 14/198820 |
Document ID | / |
Family ID | 51525800 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140267951 |
Kind Code |
A1 |
LEE; Joo-Hoon ; et
al. |
September 18, 2014 |
DIGITIZER AND METHOD OF MANUFACTURING THE SAME
Abstract
A method of manufacturing a digitizer includes forming a circuit
layer that detects an input, forming a magnetic field shielding
layer that contains disoriented magnetic powder, disposing an
adhesive between the circuit layer and the magnetic field shielding
layer, and hot pressing the circuit layer and the magnetic field
shielding layer so as to orient the magnetic powder.
Inventors: |
LEE; Joo-Hoon; (Gyeonggi-do,
KR) ; PARK; Sung-Ha; (Gyeonggi-do, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Gyeonggi-do |
|
KR |
|
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Gyeonggi-do
KR
|
Family ID: |
51525800 |
Appl. No.: |
14/198820 |
Filed: |
March 6, 2014 |
Current U.S.
Class: |
349/12 ;
29/829 |
Current CPC
Class: |
G06F 3/046 20130101;
G06F 2203/04103 20130101; Y10T 29/49124 20150115 |
Class at
Publication: |
349/12 ;
29/829 |
International
Class: |
G06F 3/046 20060101
G06F003/046 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 14, 2013 |
KR |
10-2013-0027342 |
Claims
1. A method of manufacturing a digitizer, the method comprising:
forming a circuit layer configured for sensing or detecting an
input; forming a magnetic field shielding layer that includes
disoriented magnetic powder; disposing an adhesive between the
circuit layer and the magnetic field shielding layer; and hot
pressing the circuit layer and the magnetic field shielding layer
so as to orient the magnetic powder.
2. The method of claim 1, wherein the forming of the circuit layer
further comprises: providing a Copper Clad Laminate (CCL)
comprising an insulating layer, a first conductive layer, and a
second conductive layer; and etching the first and second
conductive layers to form first and second circuits,
respectively.
3. The method of claim 2, further comprising forming a cover layer
on a surface of the first circuit.
4. The method of claim 1, wherein the forming of the magnetic field
shielding layer further comprises: dispersing magnetic powder in a
resin; and coating the resin in which the magnetic powder is
dispersed on a surface of a cover layer disposed between the
circuit layer and the magnetic field shielding layer.
5. The method of claim 4, wherein the forming of the magnetic field
shielding layer further comprises transforming the magnetic powder
into flakes, and wherein the transformed magnetic powder is
dispersed in the resin.
6. The method of claim 1, further comprising attaching a conductive
layer to a surface of the magnetic field shielding layer.
7. The method of claim 6, wherein the conductive layer is attached
to the magnetic field shielding layer by using an adhesive.
8. The method of claim 1, further comprising: disposing a cover
layer between the circuit layer and the magnetic field shielding
layer; and using the adhesive to attach the cover layer and the
circuit layer to each other.
9. The method of claim 1, wherein the adhesive is a pressure
sensitive adhesive or a thermosetting adhesive.
10. A digitizer manufactured using the method of claim 1.
11. A digitizer comprising: a circuit layer that detects or senses
an input; a magnetic field shielding layer disposed on the circuit
layer and including magnetic powder having an oriented magnetic
field; and a conductive layer disposed on the magnetic field
shielding layer.
12. The digitizer of claim 11, wherein the circuit layer further
comprises: an insulating layer; and first and second circuit
patterns disposed on opposite sides of the insulating layer.
13. The digitizer of claim 11, further comprising first and second
cover layers disposed on opposite sides of the circuit layer.
14. The digitizer of claim 12, wherein the circuit layer further
comprises: a Copper Clad Laminate (CCL) comprising an insulating
layer, a first conductive layer, and a conductive insulating layer;
and the first and second conductive layers are etched to form the
first and second circuit patterns.
15. The digitizer of claim 11, wherein the magnetic field shielding
layer is fabricated by dispersing a disoriented magnetic powder in
a resin; and coating the resin in which the magnetic powder is
dispersed on a surface of a cover layer disposed between the
circuit layer and the magnetic field shielding layer.
16. The digitizer of claim 15, wherein the magnetic field shielding
layer is fabricated by transforming the disoriented magnetic powder
into flakes, such that the transformed disoriented magnetic powder
is dispersed in the resin.
17. The digitizer of claim 11, wherein the conductive layer is
attached to the magnetic field shielding layer by an adhesive.
18. The digitizer of claim 13, wherein an adhesive is used to
attach the second cover layer and the circuit layer to each
other.
19. The digitizer of claim 17, wherein the adhesive is a pressure
sensitive adhesive or a thermosetting adhesive.
20. The digitizer of claim 18, wherein the adhesive is a pressure
sensitive adhesive or a thermosetting adhesive.
Description
CLAIM OF PRIORITY
[0001] This application claims priority under 35 U.S.C.
.sctn.119(a) to Korean Application Serial No. 10-2013-0027342,
which was filed in the Korean Intellectual Property Office on Mar.
14, 2013, the entire contents of which are incorporated herein by
reference.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates generally to a digitizer, and
more particularly, to a digitizer having a magnetic field shield
layer and a method of manufacturing the same.
[0004] 2. Description of the Related Art
[0005] In recent years, markets related to smart phones or touch
screens have been rapidly growing. Touch screens are widely used as
input devices for mobile terminals. Capacitive touch screens having
a transparent electrode and adapted to measure a change in an
electrostatic capacity generated by applied pressure from a touch
are often used. However, the capacitive touch screen requires a
user to contact the touch screen and apply a predetermined pressure
or displacement. The touch screen does not accept inputs from a
stylus or a pen. In order to overcome the foregoing shortcomings, a
touch screen technology using electromagnetic waves has been
introduced. This technology uses an Electromagnetic (EM) pointing
input unit and a display screen.
[0006] An electronic device equipped with an EM pointing input unit
requires a mounting mechanism to mount the unit to the electronic
device. Many electronic devices include batteries and circuitry,
both of which have the potential to disturb the electromagnetic
fields used by the EM pointing input unit.
[0007] Definitions: in this document, when a layer or member is
said to be formed or disposed `on` another layer or member, the
word "on" is used from the perspective of a fabrication process and
thus may be interpreted as "on a top surface" or "on a bottom
surface" of the relevant layer as, for example, either "atop" or
"underneath".
SUMMARY
[0008] An aspect of the present disclosures to provide a digitizer
which reduces or eliminates interference caused by stray
electromagnetic fields from circuit components, batteries, and
conductors.
[0009] Another aspect of the present disclosure is to provide a
digitizer which has a thin mechanical structure and is simple to
manufacture.
[0010] In accordance with another aspect of the present disclosure,
a method of manufacturing a digitizer includes: forming a circuit
layer that detects an input; forming a magnetic field shielding
layer that contains disoriented magnetic powder; disposing an
adhesive between the circuit layer and the magnetic field shielding
layer, and hot pressing the circuit layer and the magnetic field
shielding layer so as to orient the magnetic powder.
[0011] In accordance with another aspect of the present disclosure,
a digitizer includes: a circuit layer that detects an input; a
magnetic field shielding layer disposed on the circuit layer and
containing oriented magnetic field powder; and a conductive layer
disposed on the magnetic field shielding layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The above and other aspects, features, and advantages of the
present invention will be more apparent from the following detailed
description taken in conjunction with the accompanying drawings, in
which:
[0013] FIG. 1 is a functional block diagram showing a portable
terminal according to a set of exemplary embodiments of the present
invention;
[0014] FIG. 2 is a front perspective view showing the portable
terminal according to a set of exemplary embodiments of the present
invention;
[0015] FIG. 3 is a rear perspective view showing the portable
terminal according to a set of exemplary embodiments of the present
invention;
[0016] FIG. 4 is an exploded perspective view showing a touch
screen of the portable terminal;
[0017] FIG. 5 is a plan view and a corresponding cross-sectional
view exemplifying a pattern of a second sensor layer of the touch
screen;
[0018] FIG. 6 is a perspective view illustrating the touch screen
operating as a digitizer;
[0019] FIG. 7 and FIG. 8 are views illustrating principles of
magnetic field shielding;
[0020] FIG. 9 is a flowchart showing a method of manufacturing a
digitizer according to a first set of exemplary embodiments of the
present invention;
[0021] FIG. 10A and FIG. 10B is a diagrammatic representation
illustrating a method of manufacturing a digitizer according to the
first set of exemplary embodiments of the present invention;
[0022] FIG. 11 is a flowchart showing a method of manufacturing a
digitizer according to a second set of exemplary embodiments of the
present invention; and
[0023] FIG. 12A, FIG. 12B, FIG. 13A, FIG. 13B, FIG. 14A and FIG.
14B are views which illustrate methods of manufacturing a digitizer
according to the second set of exemplary embodiments of the present
invention.
[0024] Throughout the drawings, the same or like drawing reference
numerals will be understood to refer to the same or like elements,
features, and structures.
DETAILED DESCRIPTION
[0025] The present invention may be variously modified and have
various embodiments, so specific embodiments of the present
invention will be described in detail with reference to the
accompanying drawings. However, it should be understood that the
present invention is not limited to the specific embodiments
described herein and also includes all modifications, equivalents,
and replacements which fall within the scope of the present
invention.
[0026] Terms including ordinal numbers, such as first and second,
may be used to describe various constituent elements, but the
elements are not limited by these terms. The terms are used only to
distinguish one element from other elements. For example, a first
element may be named a second element without departing from the
scope of the present invention, and a second element may be named a
first element similarly. The term and/or includes a combination of
a plurality of items or any one of a plurality of items.
[0027] The terms used herein are only used to describe specific
embodiments and are not intended to limit the present invention. A
singular expression includes a plural expression, unless the
expression is explicitly defined differently in a given context. In
addition, since terms, such as "including," "comprising," and
"having" mean that one or more corresponding components may exist
unless they are specifically described to the contrary, it shall be
construed that one or more other components or additional
components may be included.
[0028] All words comprising one or more technical or scientific
terms have the same meanings that persons skilled in the art
understand ordinarily, unless these words are explicitly defined
otherwise. A word ordinarily used as defined in a dictionary shall
be construed as if the word has a meaning equal to that in the
context of a related description, and shall not be construed in an
ideal or excessively formal meaning unless it is clearly defined as
such in the present specification.
[0029] In the present invention, the term "laminated" may be
replaced by the term "disposed".
[0030] In the present invention, a terminal may be an arbitrary
device including a touch screen, and may be referred to as a
portable terminal, a mobile terminal, a communication terminal, a
portable communication terminal, or a portable mobile terminal.
[0031] For example, the terminal may be a smart phone, a mobile
phone, a gaming device, a TV, a display device, a vehicular head
unit, a notebook computer, a laptop computer, a tablet computer, a
Personal Multimedia Player (PMP), or a Personal Digital Assistant
(PDA). The terminal may be realized as a pocket-sized portable
communication terminal having a wireless communication function.
The terminal may be a flexible device or a flexible display
device.
[0032] A representative configuration of the terminal relates to a
mobile phone, and some constituent elements of the terminal may be
omitted or modified if necessary.
[0033] FIG. 1 is a functional block diagram showing a portable
terminal according to a set of exemplary embodiments of the present
invention.
[0034] Referring to FIG. 1, the portable terminal 100 may be
operatively coupled to an external electronic device (not shown) by
using at least one of a communication module 120, a connector 165,
or an earphone connection jack 167. The portable terminal 100 may,
but need not, include any of various devices such as an earphone
attached to the portable terminal 100 to be operatively coupled to
the portable terminal 100, an external speaker, a Universal Serial
Bus (USB) memory, a battery charger, a cradle/dock, an Advanced
Television Systems Committee--Mobile/Handheld (ATSC-M/H) antenna, a
Digital Media Broadcasting (DMB) antenna, a mobile payment related
device, a heath management device (for example, a blood-sugar
tester), a gaming device, or a vehicular navigation device.
Further, the electronic device may include a wirelessly-accessible
Bluetooth communication device, a Near Field Communication (NFC)
device, a WiFi direct communication device, or a Wireless Access
Point (WAP). The portable terminal 100 may be connected to one of
another portable terminal or an electronic device, for example, a
mobile phone, a smart phone, a table PC, a desktop PC, and a server
by using wired or wireless communications.
[0035] Referring to FIG. 1, the portable terminal 100 includes at
least one touch screen 190 and at least one touch screen controller
195. The portable terminal 100 includes a controller 110, a
communication module 120, a multimedia module 140, a camera module
150, an input/output module 160, a sensor module 170, a storage
unit 175, and a power supply 180.
[0036] The communication module 120 includes a mobile communication
module 121, a sub-communication module 130, and a broadcast
communication module 141.
[0037] The sub-communication module 130 includes at least one of a
wireless local area network (WLAN) module 131 or a short-range
communication module 132, and the multimedia module 140 includes at
least one of an audio playback module 142 or a video playback
module 143. The camera module 150 includes at least one of a first
camera 151 or a second camera 152. The camera module 150 may
include at least one of a barrel unit 155 for zooming in/out of a
first and/or a second camera 151 and 152, a motor 154 for
controlling zoom in/out movements of the barrel unit 155, and a
flash 153 for providing a light source for photographing. The
input/output (I/O) module 160 includes at least one of button 161,
a microphone 162, a speaker 163, a vibration element 164, a
connector 165, or an optional keypad 166.
[0038] The controller 110 may include a central processing unit
(CPU) 111, a read-only memory (ROM) 112 that stores a control
program for controlling the portable terminal 100, and a
random-access memory (RAM) 113 that stores signals or data input
from the outside of the portable terminal 100 or is used as a
memory area for operations of the portable terminal 100. The CPU
111 may include a single core, a dual core, a triple core, or a
quad core. The CPU 111, the ROM 112, and the RAM 113 may be
operatively coupled to each other through an internal bus.
[0039] The controller 110 may control the communication module 120,
the multimedia module 140, the camera module 150, the input/output
module 160, the sensor module 170, the storage unit 175, the power
supply 180, the touch screen 190, and the touch screen controller
195.
[0040] The controller 110 detects a user input applied to the touch
screen 190. The user input may be applied using an input unit 168
such as a pen or a stylus. Alternatively or additionally, the
applied input may be in the form of a finger of a user touching an
object displayed on the touch screen 190, the finger of the user
approaching an object displayed on the touch screen 109, or the
finger of the user being in closer proximity to a first object
displayed on the touch screen relative to a plurality of other
displayed objects. The controller 110 identifies an object
corresponding to a location on the touch screen 190 where a user
input is applied. The user input through the touch screen 190
includes any of a direct touch input by which an object is directly
touched, and a hovering input which is an indirect touch input by
which an object is not directly touched, but rather the object is
approached within a preset recognizable distance. For example, if
the input unit 168 is located close to and above the touch screen
190, an object located below the input unit 168 on the touch screen
190 may be selected. In the present invention, the user input
includes, in addition to a user input through the touch screen 190,
a gesture input through the camera module 150, a switch/button
input through the button 161 or the keypad 166, and a voice input
through the microphone 162.
[0041] The object or item (functional item) may be displayed on the
touch screen 190 of the portable terminal 100, and for example, may
include at least one of an application, a menu, a document, a
widget, a picture, a video, an e-mail, an SMS message, or an MMS
message. The object or functional item may be selected, executed,
deleted, canceled, stored, or changed by the user input unit 168.
One or more items may be assigned a functional meaning and may
include a button, an icon (or shortcut icon), a thumbnail image, or
a folder storing at least one object in a portable terminal. The
item may be displayed in the form of an image or text.
[0042] The shortcut icon is an image displayed on the touch screen
190 of the portable terminal 100 for a quick launch of a voice
communication, a contact address, or a menu provided in an
application or the portable terminal 100. The corresponding
application is executed if a command or a selection for executing
the shortcut icon is input.
[0043] The controller 110 may detect a user input event such as a
hovering event as the input unit 168 approaches the touch screen
190 or is located close to the touch screen 190.
[0044] If a user input event is generated for a preset item or
according to a preset method, the controller 110 performs a preset
program operation corresponding to the user input event.
[0045] The controller 110 may output a control signal to the input
unit 168 or the vibration element 164. The control signal may
include information on a vibration pattern, and the input unit 168
or the vibration element 164 generates vibrations according to the
vibration pattern. The information on the vibration pattern may
represent a vibration pattern itself and/or an identifier of a
vibration pattern. The control signal may simply include only a
request for generation of vibrations.
[0046] The portable terminal 100 may include at least one of the
mobile communication module 121, the WLAN module 131, or the
short-range communication module 132.
[0047] The mobile communication module 121 may implement a wireless
connection between the portable terminal 100 and an external
electronic device by using at least one or a plurality of antennas
(not shown) under the control of the controller 110. The mobile
communication module 121 transmits and receives wireless signals
for a voice communication, a video communication, a short message
(SMS) or a multimedia message (MMS) to and from a mobile phone (not
shown) having a phone number input to the portable terminal 100, a
smart phone (not shown), a tablet PC or another electronic device
(not shown).
[0048] As described previously, the sub-communication module 130
may include at least one of the WLAN module 131 or the short-range
communication module 132. For example, the sub-communication module
130 may include only the WLAN module 131, only the short-range
communication module 132, or both the WLAN module 131 and the
short-range communication module 132.
[0049] The WLAN module 131 may be connected to the Internet in an
area where a Wireless Access Point (WAP) (not shown) is installed
under the control of the controller 110. The wireless LAN module
131 may support a wireless LAN standard, such as any of the IEEE
802.11x series of standards developed by the Institute of
Electrical and Electronics Engineers (IEEE). The short-range
communication module 132 may perform wireless near-field
communications between the portable terminal 100 and the external
electronic device under the control of the controller 110. The near
field communication method may include any of a Bluetooth
communication, an Infrared Data Association (IrDA) communication, a
WiFi-Direct communication, and a Near Field Communication
(NFC).
[0050] The controller 110 may transmit a control signal according
to a vibration pattern to the input unit 168 through the
sub-communication module 130.
[0051] The broadcast communication module 141 may receive
broadcasting signals (for example, a TV broadcasting signal, a
radio broadcasting signal, or a data broadcasting signal)
transmitted from a broadcasting station, as well as optional
broadcast-added information (for example, an Electronic Program
Guide (EPG), an Electronic Service Guide (ESG), or Radio Data
System (RDS) text) under the control of the controller 110 through
a broadcast communication antenna.
[0052] The multimedia module 140 may include an audio playback
module 142 or a video playback module 143. The audio playback
module 142 may reproduce a digital audio file (for example, a file
whose extension is mp3, wma, ogg, or way) that is stored in or
received from the storage unit 175 under the control of the
controller 110. The video playback module 143 may reproduce a
digital video file (for example, a file whose extension is mpeg,
mpg, mp4, avi, mov, or mkv) that is stored in or received from the
storage unit 175 under the control of the controller 110.
[0053] The multimedia module 140 may, but need not, be integrated
with the controller 110.
[0054] The camera module 150 may include at least one of a first
camera 151 and a second camera 152 for photographing a still image
or a video under the control of the controller 110. The camera
module 150 may include at least one of a barrel unit 155 for
performing zooming in/out to photograph a subject, a motor 154 for
controlling movements of the barrel unit 155, and a flash 153 for
providing an auxiliary light source that may be used to photograph
a subject. Illustratively, the first camera 151 may be disposed on
a front surface of the portable terminal 100 and the second camera
152 may be disposed on a rear surface of the portable terminal
100.
[0055] The first and second cameras 151 and 152 may include various
lens systems and image sensors. The first and second cameras 151
and 152 convert optical signals input (or captured) through the
lens systems into electrical image signals and output the image
signals to the controller 110. A user may photograph a video or a
still image through the first and second cameras 151 and 152.
[0056] The I/O module 160 may, but need not, include at least one
of the following: at least one button 161, at least one microphone
162, at least one speaker 163, at least one vibration element 164,
the connector 165, the keypad 166, the earphone connecting jack
167, and the input unit 168. The I/O module 160 is not limited to
any of the foregoing items, as, a cursor control such as a mouse, a
track ball, a joystick or a cursor direction key may be used to
implement the I/O module 160 to control a movement of a cursor on
the touch screen 190.
[0057] The button 161 may be formed on a front surface, a side
surface, or a rear surface of the housing (case) of the portable
terminal 100, and may include at least one of a power/lock button,
a volume button, a menu button, a home button, a back button, or a
search button.
[0058] The microphone 162 receives a voice or a sound to generate
an electrical signal under the control of the controller 110.
[0059] The speaker 163 may output a sound or acoustic vibrations
corresponding to various signals or data (for example, wireless
data, broadcast data, digital audio data, and digital video data)
to the surrounding environment of the portable terminal 100 under
the control of the controller 110. The speaker 163 may output one
or more sounds. For example, a first beep or other audible
annunciation corresponding to an incoming voice communication may
be provided, as well as a second beep or audible annunciation
corresponding to a voice communication connecting indication. The
speaker 163 may also output and a voice of a counterpart user
engaging in the now-connected voice communication. One or a
plurality of speakers 163 may be provided at a location or
locations of the housing of the portable terminal 100.
[0060] The vibration element 164 may convert an electrical signal
into a mechanical vibration under the control of the controller
110. For example, when the portable terminal 100 in a vibration
mode receives a voice or video call from another device (not
shown), the vibration element 164 may be activated. One or a
plurality of vibration elements 164 may be provided within the
housing of the portable terminal 100. The vibration element 164 may
be operated to correspond to a user input received or accepted
through the touch screen 190.
[0061] The connector 165 may be used as an interface for connecting
the portable terminal 100 to an external electronic device or a
power source (not shown). The controller 110 may transmit data
stored in the storage unit 175 of the portable terminal 100 or
receive data from an external electronic device through a cable
connected to the connector 165. The portable terminal 100 may
receive electric power from a power source through a wired cable
connected to the connector 165, or a battery (not shown) provided
within the portable terminal 100 may be charged by using a power
source.
[0062] The keypad 166 may receive or accept a key input from the
user to control the portable terminal 100. The keypad 166 includes
a physical keypad (not shown) provided by the portable terminal 100
or a virtual keypad (not shown) provided by the touch screen 190.
The physical keypad provided by the portable terminal 100 may be
excluded.
[0063] An earphone (not shown) may be inserted into the earphone
connecting jack 167 for connection to the portable terminal
100.
[0064] The input unit 168 may be inserted into the portable
terminal 100 to be secured while the portable terminal 100 is not
in use. The input unit 168 may be extracted or separated from the
portable terminal 100 during use thereof. An attachment/detachment
recognition switch 169 activated in response to mounting and
attachment as well as detachment of the input unit 168 is provided
in one area of the interior of the portable terminal 100 into which
the input unit 168 is inserted. The attachment/detachment
recognition switch 169 may output a first signal corresponding to
mounting of the input unit 168 to the controller 110 and a second
signal corresponding to separation of the input unit 168 and the
controller 110. Alternatively or additionally, the switch may be
placed into a first state corresponding to mounting of the input
unit 168 to the controller 110, wherein the switch is placed into a
second state corresponding to separation of the input unit 168 from
the controller 110. The first state may, but need not, be a
substantially open circuit and the second state may, but need not,
be a substantially closed circuit. Alternatively, the first state
may, but need not, be a substantially closed circuit and the second
state may, but need not, be a substantially open circuit. The
attachment/detachment recognition switch 169 may be configured to
directly or indirectly contact the input unit 168 when the input
unit 168 is mounted. Accordingly, the attachment/detachment
recognition switch 169 may generate a signal corresponding to
mounting or separation of the input unit 168 (that is, a signal for
reporting mounting or separation of the input unit 168). The
corresponding signal is output to the controller 110 based on a
contact with the input unit 168. Alternatively, the
attachment/detachment recognition switch 169 may change from a
first state to a second state to thereby cause generation of a
signal by the controller 110 or another circuit element.
[0065] The sensor module 170 includes at least one sensor for
detecting a state of the portable terminal 100. For example, the
sensor module 170 may include at least one of: a proximity sensor
(not shown) for detecting an approach of a user to the portable
terminal 100, a luminance sensor (not shown) for detecting an
amount of light around the portable terminal 100, a motion sensor
(not shown) for detecting an operation of the portable terminal 100
(for example, rotation of the portable terminal 100, and
acceleration or vibration of the portable terminal 100), a
geomagnetic sensor (not shown) for detecting a point of a compass
of the portable terminal 100 by using a magnetic field of the
earth, a gravity sensor (not shown) for detecting an operational
direction of gravity, an altimeter (not shown) for measuring the
pressure of the atmosphere to detect an altitude of the portable
terminal 100, or a GPS module 157.
[0066] The GPS module 157 may receive electric waves from a
plurality of GPS satellites (not shown) in orbit around the Earth,
and may calculate a position of the portable terminal 100 by using
arrival times for a plurality of RF signals transmitted by the GPS
satellites and received by the portable terminal 100.
[0067] The storage unit 175 may store signals or data input or
output by any of the communication module 120, the multimedia
module 140, the camera module 150, the input/output module 160, the
sensor module 170 or the touch screen 190 under the control of the
controller 110. The storage unit 175 may store a control program
for control of the portable terminal 100 or the controller 110. The
storage unit 175 may also store one or more applications.
[0068] As used herein, the term "storage unit" is used to refer to
the storage unit 175, the ROM 112 in the control unit 110, the RAM
113, an arbitrary data storage unit such as a memory card (for
example, an SD card or a memory stick) mounted to the portable
terminal 100. The storage unit 175 may include a nonvolatile
memory, a volatile memory, a Hard Disk Drive (HDD), a Solid State
Drive (SSD), or any of various combinations thereof.
[0069] The storage unit 175 may store navigational information,
video communications, one or more games, images used by
applications for providing various functions such as an alarm
application based on time, Graphical User Interfaces (GUIs) related
to one or more user applications, user information, one or more
documents, one or more databases, data related to a method of
processing a touch input, background images (a menu screen, a
standby screen, and the like), operating programs necessary for
driving the portable terminal 100, or images photographed by the
camera module 150.
[0070] The storage unit 175 is a non-transitory medium readable by
a machine (for example, a computer). The term machine-readable
medium may be defined as a non-transitory medium which provides
data or instructions or both to a machine so that the machine can
perform one or more specific functions. The storage unit 175 may
include a nonvolatile medium, or a volatile medium, or a
combination of a volatile medium and a non-volatile medium. All of
the mediums should be concrete, tangible, and non-transitory so
that the commands transferred by the mediums can be detected by a
physical device that reads the commands into the machine.
[0071] The machine-readable medium includes at least one of a
floppy disk, a flexible disk, a hard disk, a magnetic tape, a
Compact disk Read Only Memory (CDROM), an optical disk, a punch
card, a paper tape, a RAM, a Programmable Read Only Memory (PROM),
an Erasable PROM (EPROM), and a flash-EPROM, but is not limited
thereto.
[0072] The power supply 180 may supply electric power to one or a
plurality of batteries disposed in the housing of the portable
terminal 100 under the control of the controller 110. The one or
plurality of batteries supply electric power to the portable
terminal 100. The power supply 180 may supply the electric power
input from an external power source to the portable terminal 100
through a wired cable connected to the connector 165. Alternatively
or additionally, the power supply 180 may supply the electric power
wirelessly input from an external power source to the portable
terminal 100 through a wireless charging technology.
[0073] The portable terminal 100 may include at least one touch
screen 190 for providing graphical user interfaces corresponding to
any of various services (for example, voice communication, data
transmission, listening to or viewing broadcasts, and
photographing) to the user.
[0074] The touch screen 190 may output an analog signal
corresponding to at least one user input applied to a graphical
user interface displayed on the touch screen 190 and accepted by
the touch screen controller 195.
[0075] The touch screen 190 may receive at least one user input
applied by a human body (for example, a finger including a thumb)
of the user, or applied by the input unit 168 (for example, a
stylus pen or an electric pen).
[0076] The touch screen 190 may receive a continuous movement (that
is, a drag input) of a single touch. The touch screen 190 may
output an analog signal corresponding to a continuous movement of
an input touch to the touch screen controller 195.
[0077] As discussed previously, the touch screen 190 may accept
user input in the form of a contact of the touch screen 190 with a
finger or the input unit 168. Alternatively or additionally, the
touch screen 190 may accept user input in the form of a noncontact
method (for example, the case of locating an applied user input
unit within a specified minimum distance (for example, 1 cm) from
the touch screen 190 by which the user input unit can be detected
without any direct contact with the touch screen 190). The distance
or interval by which the user input unit is recognized by the touch
screen 190 may be selected, adjusted, or changed according to a
desired performance parameter or structure of the portable terminal
100. In particular, the touch screen 190 may be configured such
that values (for example, voltage values or current values which
are analog values) detected by a direct touch event by a contact
with the user input unit 168, and values detected an indirect touch
event (that is, a hovering event) may be output differently or
output in such a way so that the direct touch event and the
indirect touch event may be distinguished from one another based
upon the detected values.
[0078] The touch screen 190 may be realized, for example, using a
resistive method, a capacitive method, an infrared method, an
acoustic wave method, or any of various combinations thereof.
[0079] The touch screen 190 may include at least two touch screen
panels by which a finger input and a stylus input can be detected,
respectively, such that a first input applied by a portion of a
human body such as a finger and a second input applied by a stylus
such as the input unit 168 may be detected. The at least two touch
screen panels may provide a plurality of different sensed output
values to the touch screen controller 195. For example, the touch
screen controller 195 may use the sensed output values received
from the at least two touch screen panels in order to determine
whether the touch screen 190 has accepted an input that was applied
by a finger, versus an input that was applied by the input unit
168. Alternatively or additionally, the touch screen 190 may have a
structure in which a capacitive touch screen panel and an
Electromagnetic Resonance (EMR) type touch panel are combined.
Since the touch screen 190 may include touch keys such as a menu
button 161b (FIG. 2) and a back button 161c, a finger input applied
to the touch screen 190 includes a touch input on the touch
key.
[0080] The touch screen controller 195 converts an analog signal
generated by the touch screen 190 in response to an accepted input
into a digital signal and transmits the digital signal to the
controller 110. The controller 110 may control the touch screen 190
by using a digital signal received from the touch screen controller
195. For example, the controller 110 may allow a shortcut icon (not
shown) or an object displayed on the touch screen 190 to be
selected or executed directly in response to a touch event or a
hovering event. Further, the touch screen controller 195 may be
integrated with the controller 110.
[0081] The touch screen controller 195 may detect or sense a value
(for example, a current value) output through the touch screen 190
to identify a hovering interval or distance as well as an input
location of the user, and may convert the identified distance value
into a digital signal (for example, a Z coordinate) to provide the
digital value to the controller 110. Further, the touch screen
controller 195 may detect or sense a value (for example, a current
value) output through the touch screen 190 so that the user input
unit 168 can detect a pressure applied to the touch screen 190, and
may convert the sensed pressure value into a digital signal to
provide the digital signal to the controller 110.
[0082] FIG. 2 is a front perspective view showing the portable
terminal according to a set of exemplary embodiments of the present
invention. FIG. 3 is a rear perspective view showing the portable
terminal according to a set of exemplary embodiments of the present
invention.
[0083] Referring to FIGS. 2 and 3, the touch screen 190 is disposed
at a center of a front surface 101 of the portable terminal 100.
The touch screen 190 may, but need not, be formed to occupy almost
the entire area of the front surface 101 of the portable terminal
100. FIG. 2 shows that a main home screen is displayed on the touch
screen 190. The main home screen may be the first screen displayed
on the touch screen 190 when the power of the portable terminal 100
is switched on. Further, when the portable terminal 100 has
different home screens of several pages, the main home screen may
be the first home screen of the home screens of several pages.
Shortcut icons 191-1, 191-2, and 191-3 are used for executing
frequently used applications. A main menu switching key 191-4 is
provided. A current time, and current weather conditions may be
displayed on the home screen. If a user selects the main menu
switching key 191-4, a menu screen is displayed on the touch screen
190. Further, a status bar 192 for displaying statuses of the
portable terminal 100 such as a battery charging state, an
intensity of a received signal, and a current time may be formed,
for example, at an upper end of the touch screen 190.
[0084] Touch keys such as a home button 161a, a menu button 161b,
and a back button 161c, mechanical buttons or a combination thereof
may be formed below the touch screen 190. Further, the touch keys
may be formed as parts of the touch screen 190.
[0085] The home button 161a may be used to display the main home
screen on the touch screen 190. For example, If the home button
161a is selected while another home screen or menu screen different
from the main home screen is displayed on the touch screen 190, the
main home screen may be displayed on the touch screen 190. If the
home button 161a is selected while one or more applications are
being executed on the touch screen 190, the main home screen shown
in FIG. 2 may be displayed on the touch screen 190. The home button
161a may be used to display recently used applications on the touch
screen 190 or display a task manager.
[0086] The menu button 161b provides a connection menu that can be
displayed on the touch screen 190. For purposes of illustration,
the connection menu may include any of a widget adding menu, a
background changing menu, a search menu, an edition menu, and an
environment setting menu.
[0087] The back button 161c may be used to display a screen
executed shortly before the currently executed screen, or may be
used to end the most currently used application.
[0088] The first camera 151, the luminance sensor 170a, and the
proximity sensor 170b may be disposed at a periphery of the front
surface 101 of the portable terminal 100. The second camera 152,
the flash 153, and the speaker 163 may be disposed on the rear
surface 103 of the portable terminal 100.
[0089] For example, a power/lock button 161d, a volume button 161e
having a volume up button 161f and a volume down button 161g, a
terrestrial Advanced Television Systems Committee--Mobile/Handheld
(ATSC-M/H) antenna 141a for receiving broadcasts, and one or a
plurality of microphones 162 may be disposed on a side surface of
the portable terminal 100. The ATSC-M/H antenna 141a may be fixed
to or detachably mounted to the portable terminal 100. A connector
165 may be formed, for example, on a side surface of a lower end of
the portable terminal 100. The connector 165 may have a plurality
of electrodes and may be connected to an external device. An
earphone connection jack 167 may be formed on a side surface of an
upper end of the portable terminal 100. An earphone may be inserted
into the earphone connection jack 167.
[0090] An input unit 168 may be mounted to a side surface of a
lower end of the portable terminal 100. The input unit 168 may be
inserted into and kept in the portable terminal 100 while the input
unit 168 is not in use. The input unit 168 may be extracted and
separated from the portable terminal 100 during use of the portable
terminal 100.
[0091] FIG. 4 is an exploded perspective view showing a main
configuration of a touch screen. As shown, the touch screen 190 has
a configuration in which a touch screen 210 for detecting a finger
input, a display unit 220 for displaying a screen, and a digitizer
230 for detecting a pen input are attached to each other or are
sequentially laminated to be partially spaced apart from each other
from top to bottom. The touch panel 210 and the digitizer 230 may
be referred to as a first and a second touch panel,
respectively.
[0092] The display unit 220 includes a plurality of pixels and
displays an image through the pixels. The display unit 220 may
include one or more of a Liquid Crystal Display (LCD), an Organic
Light Emitting Diode (OLED), or an LED.
[0093] The touch panel 210 includes a window 211 exposed to a front
surface of the portable terminal 100, and a second sensor layer 212
for recognizing information (a location or an intensity) of a
finger input. The second sensor layer 212 may be laminated on the
window while being laminated on a separate substrate or may be
directly laminated on the window 211. The touch panel 210 may be
configured to provide touch keys such as a menu button 161b and a
back button 161c disposed below a screen exposed to the user.
[0094] The upper surface of the window 211 forms at least a portion
of the front surface of the touch screen 190 exposed to the
outside. The window 211 may be formed of an insulating material
which is substantially transparent to visible rays. An example of
the insulating material may include a synthetic resin such as
polyimide and polyethylene terephthalate or plastic.
[0095] A hard coating layer having a high hardness for preventing a
scratch may be laminated on an upper surface of the window 211. The
hard coating layer may, but need not, have both a hardness
improving function and a glare preventing function. For example,
the hard coating layer may be formed of a material obtained by
adding a light scattering agent to a general hard coating
agent.
[0096] The second sensor layer 212 includes a sensor for
recognizing a location of a first input if a portion of a human
body such as a finger contacts a surface of the window 211 (FIG.
4), and the second sensor layer 212 has preset patterns for this.
The second sensor layer 212 may have various patterns such as a
linear grid pattern or a diamond pattern, for example. The second
sensor layer 212 may be laminated on a lower surface of the window
211, or a lower end (lower surface) of the second sensor layer 212
may be attached to an upper end (or upper surface) of the display
unit 220 by using a transparent adhesive member.
[0097] FIG. 5 is a plan view and a corresponding cross-sectional
view illustrating a pattern of the second sensor layer. The second
sensor layer 212 includes first electrode lines 310 and second
electrode lines 320. The cross-sectional view displayed at a lower
portion of FIG. 5 shows continuously disposed first electrode lines
310 TX1, TX2, ad TX3, and a second electrode line 320 RX.
[0098] The first electrode lines 310 extend along a first direction
(for example, the x-axis or horizontal direction) and are disposed
at the same interval or different intervals in a second direction
(for example, the y-axis or vertical direction) crossing the first
direction perpendicularly to the first direction.
[0099] The second electrode lines 320 extend along the second
direction crossing the first direction perpendicularly to the first
direction, and are disposed at the same interval or different
intervals along the first direction.
[0100] In order to electrically insulate the first electrode lines
310 from the second electrode lines 320, an insulating layer 330 is
disposed between the first electrode lines 310 and the second
electrode lines 320. A suitable material for the insulating layer
330 may include, for example, an insulating dielectric material
such as SiO.sub.2.
[0101] The second sensor layer 212 may be formed of a conductive
material which is substantially transparent to visible rays of
light. An example of a suitable conductive material may include a
carbon containing organic material such as Carbon Nano Tube (CNT)
or graphene.
[0102] In order to perform a sensing function, a scan signal having
a predetermined waveform is applied to the second sensor layer 212.
If a portion of a human body such as a finger contacts a surface of
the window 211, a detection signal whose waveform is changed due to
an electrostatic capacity between the second sensor layer 212 and
the portion of the human body is generated. The controller 110
analyzes the detection signal to recognize a contact and a contact
location of the portion of the human body. For example, if the
portion of the human body contacts the touch screen 190 (FIG. 2),
an electrostatic capacity of a corresponding sensing point 340
(FIG. 5) increases. The controller 110 detects generation of a
finger touch event based on a detection signal having a peak value
above a threshold value (or a minimum value below a threshold
value), or detects a finger input location. The threshold value may
be empirically set as a value for distinguishing noise from a
normal signal, and for example, may be set to a voltage of above 0
V or an electric capacity of above 0 pf. Meanwhile, a finger is an
example of the portion of the human body, and any unit that can
provide an electrostatic capacity between the second sensor layer
212 and the unit may be used.
[0103] In order to perform a sensor function, voltages (that is,
scan signals) having predetermined waveforms are sequentially
applied from the touch screen controller 195 (FIG. 1) to the first
electrode lines 310 (FIG. 5), and the second electrode lines 320
outputs detection signals due to the scan signals to the touch
screen controller 195. Points where the first and second electrode
lines 310 and 320 cross each other become sensing points 340, and
the sensing points 340 are disposed in a matrix structure in the
illustrative example of FIG. 5. That is, a finger input location is
determined by one of the locations of the sensing points 340. If
the portion of the human body contacts a surface of the window 211,
an entire electrostatic capacity of a corresponding sensing point
340 varies due to an electrostatic capacity between the second
sensor layer 212 and the portion of the human body. Voltage
waveforms of the detection signals output from the second electrode
lines 320 vary due to the change in the electrostatic capacity. An
input location and/or an input intensity of a finger input are
recognized from the detection signals whose voltage waveforms have
been modified by the applied finger input.
[0104] FIG. 6 is a perspective view illustrating the operation of
the digitizer that was previously described in conjunction with
FIG. 4.
[0105] The digitizer 230 may be an Electromagnetic (EM) touch
panel, and includes a first sensor layer 410, a magnetic field
shielding layer 420, and a conductive layer 430. The main board 440
disposed below the digitizer 230 may be a printed circuit board in
which various circuits such as the controller 110, the
communication module 120, the multimedia module 140, the
input/output module 160, the sensor module 170, the storage unit
175, and the power supply 180 are mounted or connected to an upper
surface or a lower surface thereof.
[0106] The first sensor layer 410 includes first and second loop
parts 510 and 520, and is operated under the control of the touch
screen controller 195, The first sensor layer 410 outputs detected
signals to the touch screen controller 195. The first loop part 510
includes a plurality of first loops 511 and the second loop part
520 includes a plurality of second loops 521.
[0107] A magnetic field or electromagnetic signal 404 emitted by
the input unit 168 may be absorbed by the loops 511 and 521, and
accordingly, a portion of the digitizer 230 in closest proximity to
the input unit 168 may be identified.
[0108] Further, the loops 511 and 521 may generate magnetic fields
according to an input current, and the generated magnetic fields
may be absorbed by the input unit 168. The input unit 168 may emit
the absorbed magnetic fields again, and the magnetic fields emitted
from the input unit 168 may be absorbed by the loops 511 and
521.
[0109] The first loop part 510 and the second loop part 520 may be
disposed perpendicular to each other.
[0110] The first loop part 510 extends relatively long in the
y-axis direction rather than in the x-axis direction, and
accordingly is used to detect an x-axis coordinate of a pen input
location.
[0111] The second loop part 520 extends relatively long in the
x-axis direction rather than in the y-axis direction, and
accordingly is used to detect a y-axis coordinate of a pen input
location.
[0112] The first and second loops 511 and 521 detect an
electromagnetic signal 404 having a predetermined frequency output
from the input unit 168 in the form of an electrical signal. The
first and second loops 511 and 521 output the detected
electromagnetic signal 404 to the touch screen controller 195.
[0113] The input unit 168, when placed in proximity to the
digitizer 230, generates an electromagnetic signal according to an
operation of a resonant circuit 401 including a coil 402 and a
capacitor 403, and outputs the electromagnetic signal.
[0114] The input unit 168 is one illustrative embodiment, as any
unit capable of outputting an electromagnetic signal may be
used.
[0115] The conductive layer 430 prevents the first sensor layer 410
and a circuit or a peripheral circuit of the main board 440 from
interfering with each other due to stray magnetic fields, and is
laminated on a lower surface of the electromagnetic field shielding
layer 420. The conductive layer 430 may be laminated on an entire
lower surface and an entire or portion of side surface of the
digitizer 230. Then, the conductive layer 430 may surround at least
an entire side surface of the first sensor layer 410. That is, the
conductive layer 430 may have a box structure having an opened
upper end like a general bracket. The conductive layer 430 prevents
a magnetic field generated in a circuit or a peripheral circuit of
the main board 440 from reaching the first sensor layer 410.
[0116] FIGS. 7 and 8 are views that illustrate the basic principles
of magnetic field shielding.
[0117] Referring to FIG. 7, a coil 620 connected to an AC power
source 610 generates a first magnetic field 630.
[0118] If a magnetic field is applied to the conductive layer 640,
an eddy current 650 is generated. The eddy current 650 generates a
second magnetic field 660 in an opposite direction to the applied
first magnetic field 630, and accordingly, an intensity of the
first magnetic field 630 is reduced by an offset interference by
the second magnetic field 660.
[0119] For this reason, if an intensity of the magnetic field
applied to the digitizer 230 is reduced, a maximum distance by
which the digitizer 230 recognizes an input unit becomes shorter,
which increases the possibility that the digitizer 230 will
malfunction or not operate properly.
[0120] Referring to FIG. 8, the magnetic field shielding layer 420
is disposed between the first sensor layer 410 and the conductive
layer 430. Almost all of the first magnetic field 404 having passed
through the first sensor layer 410 flows through the magnetic field
shielding layer 420 to significantly reduce an intensity of a
residual magnetic field 405 having passed through the magnetic
field shielding layer 420 and having reached the conductive layer
430. Thus, an intensity of the second magnetic field 406 generated
by the residual magnetic field 405 is also significantly reduced.
In this case, since the first magnetic field 405 fails to reach the
conductive layer 430, an eddy current is not generated in the
conductive layer 430, and the first magnetic field remains
intact.
[0121] Unlike this example, the conductive layer 430 may be
omitted, in which case since an offset interference may be
generated by the eddy current due to a conductive element located
around the digitizer 230, the magnetic field shielding layer 420 is
used to restrain the offset interference.
[0122] FIG. 9 is a flowchart showing a method of manufacturing a
digitizer according to a first set of embodiments of the present
invention, and FIG. 10 is a view for explaining the method of
manufacturing a digitizer.
[0123] The method of manufacturing a digitizer includes steps S10
to S20. FIG. 10A shows an arrangement of layers which correspond to
step S10 of FIG. 9, and FIG. 10B shows this arrangement of layers
upon performance of step S20 of FIG. 9.
[0124] Step S110 is a step of temporarily bonding first and second
cover layers 20 and 30 to a circuit layer 10. The first and second
cover layers 20 and 30 are temporarily bonded to the circuit layer
10 by using first and second adhesive layers 40 and 41. That is,
the temporary bonding step is a step of temporarily bonding the
first and second cover layers 20 and 30 to the circuit layer 10
before hot pressing. The circuit layer 10 includes an insulating
layer 12. First and second conductive circuits 11 and 13, laminated
on opposite surfaces of the insulating layer 12, constitute loop
parts 510, 520 (FIG. 6). The first and second circuits 11 and 13
(FIGS. 10A and 10B) have preset conductive circuit patterns,
respectively. Further, in the illustrated layered structure, any of
the adjacent layers may be expressed to be laminated on or attached
to each other.
[0125] The circuit layer 10 may be formed by preparing a Copper
Clad Laminate (CCL) including an insulating layer 12 of a Polyimide
(PI) material, a first conductive layer of a copper material
laminated on a first surface of the insulating layer 12, and a
second conductive layer of a copper material laminated on a second
surface of the insulating layer located on an opposite side of the
first surface, and etching the first and second conductive layers
by conventional photolithography such that the first and second
conductive layers have patterns of the loop parts 510, 520 (FIG.
6). The photo-etched first and second conductive layers form first
and second circuits 11 and 13 (FIGS. 10A and 10B).
[0126] The first cover layer 20 may be formed of a polyimide
material, and may be bonded to a surface of the first circuit 11 by
using a first adhesive layer 40 such as a pressure sensitive
adhesive or a thermosetting adhesive.
[0127] The second cover layer 30 may be formed of a polyimide
material, and may be bonded to a surface of the second circuit 13
by using a second adhesive layer 41 such as a PSA or a
thermosetting adhesive.
[0128] The magnetic field shielding layer 420a may be coated on a
surface of the second cover layer 30.
[0129] The magnetic field shielding layer 420a may have a structure
in which magnetic powder 422 in the form of thin plate-shaped
flakes is dispersed disorderly (or at random) in an insulating
and/or adhesive resin 421. That is, the magnetic field shielding
layer 420a may contain disoriented magnetic powder 422.
[0130] For example, the magnetic field shielding layer 420a may be
formed by transforming magnetic powder such as one or more of a
ferrite, Molypermalloy Powder (MPP), an Fe--Si--Al series material
(Sandust), or an Ni--Fe series material (Highflux) into flakes,
adding and dispersing the transformed magnetic powder 422 into an
insulating and/or adhesive resin (or adhesive) 421, and coating the
resin 421 in which the magnetic powder 422 is dispersed on a
surface of the second cover layer 30. The resin 421 in which the
magnetic powder 422 is coated on the second cover layer 30 forms
the magnetic field shielding layer 420a.
[0131] Step S20 is a step of hot pressing the circuit layer 10 and
the first and second cover layers 20 and 30. The circuit layer 10
and the first and second cover layers 20 and 30 may be hot pressed
by using a hot press apparatus. The hot pressing refers to applying
a pressure at a high temperature, for example, a temperature in the
approximate range of 120 to 280.degree. C.
[0132] The thicknesses of the magnetic field shielding layer 420a
and the adhesive layers 40 and 41 are reduced through the hot
pressing process. The magnetic powder 422 that was dispersed
disorderly or randomly is now arranged (that is, oriented) in a
predetermined direction in the magnetic field shielding layer 420
through the hot pressing process. The magnetic field shielding
characteristics of the oriented magnetic field shielding layer 420
are significantly improved relative to the randomly or disorderly
orientation of the magnetic powder 422. The magnetic field
shielding layer 420 having undergone the hot pressing process may
have a permeability of 100 H/m to 200 H/m in a DC band, and may
have a permeability of 100 H/m to 150 H/m in a band of 500 KHz
(531.25 KHz, 562.5 KHz, and 593.75 KHz). The magnetic field
shielding layer 420 passes a geomagnetic field therethrough and
does not influence an operation of a geomagnetic sensor. For
example, the magnetic field shielding layer 420 may have a
thickness of 50 .mu.m to 100 .mu.m.
[0133] The circuit layer 10 and the first and second cover layers
20 and 30 may constitute the first sensor layer 410.
[0134] FIG. 11 is a flowchart showing a method of manufacturing a
digitizer according to a second set of embodiments of the present
invention. FIGS. 12 to 14 are views for explaining the method of
manufacturing a digitizer according to the second set of
embodiments of the present invention.
[0135] The method of manufacturing a digitizer includes steps S110
to S130.
[0136] Step S110 is a step of forming a circuit layer 710. The
circuit layer 710 including first and second circuits 711 and 713,
and a first cover layer 720 laminated on a first surface of the
circuit layer 710, are formed. Hereinafter, first and second
surfaces of the layers are located on opposite sides of the layers.
The circuit layer 710 has preset conductive circuit patterns such
as loop parts 510, 520 (FIG. 6). In the layered structure of FIGS.
12A and 12B, adjacent layers may be expressed to be directly
laminated on or attached to each other.
[0137] Referring to FIG. 12A, the circuit layer 710 includes an
insulating layer 712, a conductive first circuit 711 laminated on a
first surface of the insulating layer 712, and a conductive second
circuit 713 laminated on a second surface of the insulating layer
712 located on an opposite side of the first surface.
[0138] Referring to FIG. 12B, an insulating first cover layer 720
may be laminated on a surface of the first circuit 711.
[0139] For example, the first circuit 711 and the first cover layer
720 may be attached to each other by disposing an adhesive layer
such as one or more of a Pressure Sensitive Adhesive (PSA), an
adhesive sheet, a bonding sheet, or a thermosetting adhesive
between the first circuit 711 and the first cover layer 720 of a
polyimide material, and pressing the first circuit 711 and the
first cover layer 720. The first circuit 711 and the first cover
layer 720 may be hot pressed by using the PSA or the thermosetting
adhesive and a hot press apparatus. The first circuit 711 and the
first cover layer 720 may be attached to each other through a
UV-curable adhesive irradiated with UV rays.
[0140] Step 120 is a step of forming a magnetic field shielding
layer 420a and a conductive layer 430. The magnetic field shielding
layer 420a is laminated on a second surface of an insulating second
cover layer 730 and a conductive layer 430 is laminated on a
surface of the magnetic field shielding layer 420a.
[0141] Referring to FIG. 13A, the magnetic field shielding layer
420a has a structure in which magnetic powder 422 in the form of
thin plate-shaped flakes is dispersed disorderly (or at random) in
an insulating and/or adhesive resin 421. That is, the magnetic
field shielding layer 420a contains disoriented magnetic powder
422.
[0142] Referring to FIG. 13B, while the magnetic field shielding
layer 420a is not dried, an aluminum or magnesium conductive layer
430 in the form of a film is attached to a surface of the magnetic
field shielding layer 420a.
[0143] Note that, in contrast to the example of FIG. 13B, the
conductive layer 430 may, but need not, be attached to a surface of
the magnetic field shielding layer 420a by using an adhesive. Then,
the conductive layer 430 may be attached to a surface of the
magnetic field shielding layer 420a by using an adhesive such as a
PSA or a thermosetting adhesive so that the conductive layer 430
may be hot pressed during the hot pressing of the magnetic field
shielding layer 420a.
[0144] Step S130 is a step of attaching the magnetic field
shielding layer 420a and the circuit layer 710. The magnetic field
shielding layer 420a and the circuit layer 710 may be hot pressed
by using the PSA or the thermosetting adhesive and a hot press
apparatus.
[0145] Referring to FIG. 14A, the magnetic field shielding layer
420a and the circuit layer 710 may be arranged while the adhesive
layer 740 such as a PSA or a thermosetting adhesive is interposed
therebetween. That is, a second surface of the second circuit 713
and a first surface of the second cover layer 730 are temporarily
attached by using the adhesive layer 740.
[0146] Referring to FIGS. 14A and 14B, the magnetic field shielding
layer 420a and the circuit layer 710 are hot pressed by using a hot
press apparatus. The thicknesses of the magnetic field shielding
layer 420a and the bonding layer 740 are reduced through the hot
pressing process. Prior to performance of the hot pressing process,
the magnetic powder 422 has a randomly or disorderly dispersed
magnetic orientation. The thermal pressing process arranges or
orients the magnetic powder 422 in a predetermined direction in the
magnetic field shielding layer 420.
[0147] The first and second cover layers 720 and 730, the first and
second circuits 711 and 713, and the insulating layer 712 may
constitute the first sensor layer 410.
[0148] In contrast to the example of FIGS. 14A and 14B, after the
magnetic field shielding layer 420 is hot pressed, the conductive
layer 430 may be attached to the magnetic field shielding layer 420
by using an adhesive. The conductive layer 430 may be coated on the
magnetic field shielding layer 420 through a deposition
process.
[0149] The present invention provides a digitizer which reduces or
eliminates interference caused by stray electromagnetic fields from
external circuit components or conductors. The digitizer has a thin
structure, and is simple to manufacture.
[0150] In more detail, according to a set of illustrative
embodiments of the present invention, the need to perform a
separate process or a special step of orienting magnetic powder may
be eliminated. The magnetic powder is automatically oriented when a
magnetic field shielding layer and a circuit layer are hot pressed.
A separate cutting and attaching process for a cover layer and the
magnetic field shielding layer can be excluded. In addition, a
digitizer manufacturing process may be automated and simplified.
The digitizer may be designed to have a thin structure, low cost,
and high performance by directly coating the magnetic field
shielding layer on the cover layer and excluding a separate bonding
film for attachment of the magnetic field shielding layer.
[0151] Although the exemplary embodiments of the present invention
have been described in detail with reference to specific examples,
various modification can be made without departing from the scope
of the present invention. Thus, the scope of the present invention
is not determined by the above-described embodiments and should be
determined by the claims and their equivalents.
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