U.S. patent application number 16/744429 was filed with the patent office on 2020-08-06 for touch apparatus.
The applicant listed for this patent is HiDeep Inc.. Invention is credited to Kiryoung Jung, Bonkee Kim, Jongsik Kim, Seyeob Kim, Hwanhee Lee, Hyoungwook Woo.
Application Number | 20200249791 16/744429 |
Document ID | / |
Family ID | 1000004636987 |
Filed Date | 2020-08-06 |
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United States Patent
Application |
20200249791 |
Kind Code |
A1 |
Kim; Seyeob ; et
al. |
August 6, 2020 |
TOUCH APPARATUS
Abstract
An exemplary embodiment of the present invention provides a
touch apparatus including: a touch panel including a plurality of
first touch electrodes arranged in a first direction and a
plurality of second touch electrodes arranged in a second direction
crossing the first direction; a driver configured to apply a first
driving signal to the first touch electrodes during a first period
and a second driving signal to the second touch electrodes during a
second period subsequent to the first period; a receiver configured
to receive a detection signal from the second touch electrodes
during the first period, and a detection signal from the first
touch electrodes and the second touch electrodes during a third
period subsequent to the second period; and a controller configured
to determine a touch position based on the signal outputted from
the receiver.
Inventors: |
Kim; Seyeob; (Seongnam-si,
KR) ; Kim; Jongsik; (Seongnam-si, KR) ; Lee;
Hwanhee; (Seongnam-si, KR) ; Woo; Hyoungwook;
(Seongnam-si, KR) ; Jung; Kiryoung; (Seongnam-si,
KR) ; Kim; Bonkee; (Seongnam-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HiDeep Inc. |
Seongnam-si |
|
KR |
|
|
Family ID: |
1000004636987 |
Appl. No.: |
16/744429 |
Filed: |
January 16, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/0418 20130101;
G06F 2203/04104 20130101; G06F 3/04166 20190501; G06F 3/04162
20190501 |
International
Class: |
G06F 3/041 20060101
G06F003/041 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 1, 2019 |
KR |
10-2019-0014045 |
Claims
1. A touch apparatus comprising: a touch panel including a
plurality of first touch electrodes arranged in a first direction
and a plurality of second touch electrodes arranged in a second
direction crossing the first direction; a driver configured to
apply a first driving signal to the first touch electrodes during a
first period and a second driving signal to the second touch
electrodes during a second period subsequent to the first period; a
receiver configured to receive a detection signal from the second
touch electrodes during the first period, and a detection signal
from the first touch electrodes and the second touch electrodes
during a third period subsequent to the second period; and a
controller configured to determine a touch position based on the
signal outputted from the receiver.
2. The touch apparatus of claim 1, wherein the driver applies a
pulse signal of a first frequency to the first touch electrodes as
the first driving signal during the first period.
3. The touch apparatus of claim 2, wherein the receiver includes an
amplifier connected to each of the second touch electrodes during
the first period to amplify and output a detection signal from a
corresponding second touch electrode.
4. The touch apparatus of claim 2, wherein the driver applies a
pulse signal of a second frequency that is higher than the first
frequency to both the first touch electrodes and the touch
electrodes as the second driving signal during the second
period.
5. The touch apparatus of claim 1, wherein the receiver receives a
detection signal from both the first touch electrodes and the
second touch electrodes during the third period.
6. The touch apparatus of claim 1, wherein the driver does not
apply the second driving signal to the first touch electrodes and
the second touch electrodes during the third period.
7. The touch apparatus of claim 1, wherein the receiver includes a
plurality of differential amplifiers that simultaneously receive
detection signals from both the first touch electrodes and the
second touch electrodes during the third period.
8. The touch apparatus of claim 7, wherein the driver does not
apply the second driving signal to the first touch electrodes and
the second touch electrodes during the third period.
9. The touch apparatus of claim 8, wherein the controller
determines the third detection signal as a valid touch signal based
on whether signal strength of the third detection signal exceeds a
second threshold.
10. The touch apparatus of claim 7, wherein the differential
amplifiers include: a first differential amplifier configured to
receive detection signals from two first touch electrodes spaced by
at least one first touch electrode; and a second differential
amplifier configured to receive detection signals from two second
touch electrodes spaced by at least one second touch electrode.
11. The touch apparatus of claim 1, wherein the detection signal
includes at least one of a first detection signal generated by a
first touch object and a second detection signal generated by a
second touch object.
12. The touch apparatus of claim 11, wherein the controller
determines a detection signal as a valid touch signal based on
whether a signal strength of the detection signal received in
response to the first driving signal exceeds a first threshold
during the first period, and the first detection signal is
determined as a valid touch signal, and the first threshold is set
to filter the second detection signal.
13. The touch apparatus of claim 11, wherein the first touch object
includes at least one of a finger and a palm, and the second touch
object is a stylus pen
14. A touch apparatus comprising: a touch panel including a
plurality of first touch electrodes arranged in a first direction
and a plurality of second touch electrodes arranged in a second
direction crossing the first direction; a driver configured to
apply a first driving signal to the first touch electrodes during a
first period and a second driving signal to the second touch
electrodes during a second period subsequent to the first period; a
plurality of differential amplifiers configured to receive a
detection signal from the first touch electrodes and the second
touch electrodes during a third period subsequent to the second
period; and the controller configured to determine a touch position
based on the signal outputted from the differential amplifiers.
15. The touch apparatus of claim 14, wherein the differential
amplifiers simultaneously receive detection signals from both the
first touch electrodes and the second touch electrodes during the
third period.
16. The touch apparatus of claim 14, wherein the driver does not
apply the second driving signal to the first touch electrodes and
the second touch electrodes during the third period.
17. The touch apparatus of claim 14, wherein the differential
amplifiers receive only a third detection signal generated by the
second touch object in response to the second driving signal during
the third period.
18. The touch apparatus of claim 17, wherein the third detection
signal is determined as a valid touch signal based on whether
signal strength of the third detection signal exceeds a second
threshold.
19. The touch apparatus of claim 18, wherein the differential
amplifiers include: a first differential amplifier configured to
receive detection signals from two first touch electrodes spaced by
at least one first touch electrode; and a second differential
amplifier configured to receive detection signals from two second
touch electrodes spaced by at least one second touch electrode.
20. The touch apparatus of claim 14, wherein the detection signal
include at least one of a first detection signal generated by a
first touch object and a second detection signal generated by a
second touch object.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and benefits of Korean
Patent Application No. 10-2019-0014045 filed in the Korean
Intellectual Property Office on Feb. 1, 2019, the entire contents
of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
(a) Field of the Invention
[0002] The present disclosure relates to a touch apparatus.
(b) Description of the Related Art
[0003] Various terminals such as mobile phones, smart phones,
tablet PCs, laptop computers, digital broadcasting terminals, PDAs
(personal digital assistants), PMPs (portable multimedia players),
and navigation devices include touch sensors.
[0004] In such a terminal, a touch sensor may be disposed on a
display panel displaying an image, or may be disposed in an area of
a terminal body. As a user interacts with the terminal by touching
the touch sensor, the terminal may provide the user with an
intuitive user interface.
[0005] The user may use a stylus pen for sophisticated touch input.
The stylus pen may transmit and receive signals to and from the
touch sensor in an electrical and/or magnetic manner.
[0006] Conventionally, amplifiers corresponding to each of the
touch electrodes are provided in the touch sensor in order to
receive detection signals from the touch electrodes included in the
touch sensor.
[0007] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention and therefore it may contain information that does not
form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY OF THE INVENTION
[0008] Exemplary embodiments have been made in an effort to provide
a touch apparatus for receiving a detection signal from which a
noise component has been removed.
[0009] Exemplary embodiments have been made in an effort to provide
a touch apparatus for calculating a position of a touch input
between two adjacent touch electrodes.
[0010] Exemplary embodiments have been made in an effort to provide
a touch apparatus that detects inputs by different touch objects
with different periods within one frame.
[0011] For achieving the objects or other objects, an aspect of the
present invention provides a touch apparatus including: a touch
panel including a plurality of first touch electrodes arranged in a
first direction and a plurality of second touch electrodes arranged
in a second direction crossing the first direction; a driver
configured to apply a first driving signal to the first touch
electrodes during a first period and a second driving signal to the
second touch electrodes during a second period subsequent to the
first period; a receiver configured to receive a detection signal
from the second touch electrodes during the first period, and a
detection signal from the first touch electrodes and the second
touch electrodes during a third period subsequent to the second
period; and a controller configured to determine a touch position
based on the signal outputted from the receiver.
[0012] The driver may sequentially apply a pulse signal of a first
frequency to the first touch electrodes as the first driving signal
during the first period.
[0013] The receiver may include an amplifier connected to each of
the second touch electrodes during the first period to amplify and
output a detection signal from a corresponding second touch
electrode.
[0014] The driver may apply a pulse signal of a second frequency
that is higher than or equal to a first frequency to both first
touch electrodes and second touch electrodes as a second driving
signal during the second period.
[0015] The receiver may receive a detection signal from both the
first touch electrodes and the second touch electrodes during the
third period.
[0016] The driver may not apply the second driving signal to the
first touch electrodes and the second touch electrodes during the
third period.
[0017] The receiver may include a plurality of differential
amplifiers that simultaneously receive detection signals from both
the first touch electrodes and the second touch electrodes during
the third period.
[0018] A plurality of differential amplifiers may receive only a
third detection signal generated by the second touch object in
response to the second driving signal during the second period.
[0019] The controller may determine the third detection signal as a
valid touch signal based on whether signal strength of the third
detection signal exceeds a second threshold.
[0020] The differential amplifiers may include: a first
differential amplifier configured to receive detection signals from
two first touch electrodes spaced by at least one first touch
electrode; and a second differential amplifier configured to
receive detection signals from two second touch electrodes spaced
by at least one second touch electrode.
[0021] The detection signal may include at least one of a first
detection signal generated by a first touch object and a second
detection signal generated by a second touch object.
[0022] The controller may determine a detection signal as a valid
touch signal based on whether a signal strength of the detection
signal received in response to the first driving signal exceeds a
first threshold during the first period, and the first detection
signal may be determined as a valid touch signal, while the first
threshold may be set to filter the second detection signal.
[0023] The first touch object may include at least one of a finger
and a palm, while the second touch object may be a stylus pen.
[0024] An exemplary embodiment of the present invention provides a
touch apparatus including: a touch panel including a plurality of
first touch electrodes arranged in a first direction and a
plurality of second touch electrodes arranged in a second direction
crossing the first direction; a driver configured to apply a first
driving signal to the first touch electrodes during a first period
and a second driving signal to the second touch electrodes during a
second period subsequent to the first period; a plurality of
differential amplifiers configured to receive a detection signal
from the first touch electrodes and the second touch electrodes
during a third period subsequent to the second period; and the
controller configured to determine a touch position based on the
signal outputted from the differential amplifiers.
[0025] The differential amplifiers may simultaneously receive
detection signals from both the first touch electrodes and the
second touch electrodes during the third period.
[0026] The driver may not apply the second driving signal to the
first touch electrodes and the second touch electrodes during the
third period.
[0027] A plurality of differential amplifiers may receive only a
third detection signal generated by the second touch object in
response to the second driving signal during the second period.
[0028] The third detection signal may be determined as a valid
touch signal based on whether signal strength of the third
detection signal exceeds a second threshold.
[0029] The differential amplifiers may include: a first
differential amplifier configured to receive detection signals from
two first touch electrodes spaced by at least one first touch
electrode; and a second differential amplifier configured to
receive detection signals from two second touch electrodes spaced
by at least one second touch electrode.
[0030] The detection signal may include at least one of a first
detection signal generated by a first touch object and a second
detection signal generated by a second touch object.
[0031] Each of the first differential amplifiers of the
differential amplifiers may be connected to each of the second
touch electrodes during the first period to amplify and output a
detection signal from a corresponding second touch electrode, the
controller may determine a detection signal as a valid touch signal
based on whether a signal strength of the detection signal received
in response to the first driving signal exceeds a first threshold
during the first period, and the first detection signal may be
determined as a valid touch signal, while the first threshold may
be set to filter the second detection signal.
[0032] The first touch object may include at least one of a finger
and a palm, while the second touch object may be a stylus pen.
[0033] A frequency of the first drive signal may be less than or
equal to that of the second drive signal.
[0034] According to the exemplary embodiments, it is possible to
improve reception sensitivity of the touch input.
[0035] According to the exemplary embodiments, it is possible to
accurately calculate touch positions.
[0036] According to the exemplary embodiments, it is possible to
accurately detect inputs by different touch objects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 schematically illustrates a touch apparatus according
to an exemplary embodiment.
[0038] FIG. 2 illustrates an example in which a stylus pen is
touched on a touch apparatus according to an exemplary
embodiment.
[0039] FIG. 3 schematically illustrates a touch detection method
according to an exemplary embodiment.
[0040] FIG. 4 illustrates a waveform diagram showing an example of
a driving signal according to the touch detection method of FIG.
3.
[0041] FIG. 5 partially illustrates a touch panel and a receiver
according to a conventional art.
[0042] FIG. 6 illustrates a waveform diagram showing an example of
a reception signal received by two electrodes of the touch panel
shown in FIG. 5.
[0043] FIG. 7 partially illustrates a touch panel and a driver
according to an exemplary embodiment.
[0044] FIG. 8 illustrates a waveform diagram showing an example of
a reception signal received by two electrodes of the touch panel
shown in FIG. 7.
[0045] FIG. 9 to FIG. 11 illustrate the touch apparatus of FIG. 1
in more detail.
[0046] FIG. 12 illustrates a waveform diagram showing an example of
a driving signal and a reception signal according to the touch
detection method of FIG. 3.
[0047] FIG. 13 illustrates a part of a receiver that outputs the
reception signal of FIG. 12.
[0048] FIG. 14 illustrates a waveform diagram showing another
example of a driving signal and a reception signal according to the
touch detection method of FIG. 3.
[0049] FIG. 15 illustrates a part of a receiver that outputs the
reception signal of FIG. 14.
[0050] FIG. 16 illustrates a graph showing magnitudes of the
reception signals of FIGS. 12 and 14.
[0051] FIG. 17 and FIG. 18 illustrate touch areas of different
objects.
[0052] FIG. 19 illustrates a block diagram showing a touch
apparatus and a host that perform the driving method of FIG. 3.
[0053] FIG. 20 illustrates an example of touch data provided to a
host from a touch apparatus.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0054] The present invention will be described more fully
hereinafter with reference to the accompanying drawings, in which
exemplary embodiments of the invention are shown. As those skilled
in the art would realize, the described embodiments may be modified
in various different ways, all without departing from the spirit or
scope of the present invention.
[0055] To clearly describe the present invention, parts that are
irrelevant to the description are omitted, and like numerals refer
to like or similar constituent elements throughout the
specification.
[0056] Further, since sizes and thicknesses of constituent elements
shown in the accompanying drawings are arbitrarily given for better
understanding and ease of description, the present invention is not
limited to the illustrated sizes and thicknesses. In the drawings,
the thicknesses of layers, films, panels, regions, etc., are
exaggerated for clarity. In the drawings, for better understanding
and ease of description, the thicknesses of some layers and areas
are exaggerated.
[0057] It will be understood that when an element such as a layer,
film, region, or substrate is referred to as being "on" another
element, it can be directly on the other element or intervening
elements may also be present. In contrast, when an element is
referred to as being "directly on" another element, there are no
intervening elements present. Further, the word "over" or "on"
means positioning on or below the object portion, and does not
necessarily mean positioning on the upper side of the object
portion based on a gravity direction.
[0058] In addition, unless explicitly described to the contrary,
the word "comprise" and variations such as "comprises" or
"comprising" will be understood to imply the inclusion of stated
elements but not the exclusion of any other elements.
[0059] Hereinafter, a touch apparatus and a touch detection method
thereof according to exemplary embodiments will be described with
reference to necessary drawings.
[0060] FIG. 1 schematically illustrates a touch apparatus according
to an exemplary embodiment, and FIG. 2 illustrates an example in
which a stylus pen is touched on a touch apparatus according to an
exemplary embodiment.
[0061] Referring to FIG. 1, the touch apparatus 10 according to an
exemplary embodiment includes a touch panel 100 and a touch
controller 102 for controlling the touch panel 100. The touch
controller 102 may include first and second driver/receivers 110
and 120 and a controller 130 for transmitting and receiving a
signal to and from the touch panel 100.
[0062] The touch panel 100 includes a plurality of first touch
electrodes 111-1 to 111-m having a form extending in a first
direction, and a plurality of second touch electrodes 121-1 to
121-n having a form extending in a second direction crossing the
first direction. In the touch panel 100, the first touch electrodes
111-1 to 111-m may be arranged along the second direction, and the
second touch electrodes 121-1 to 121-n may be arranged along the
first direction. In FIG. 1, a shape of the touch panel 100 is
illustrated as a quadrangle, but the present invention is not
limited thereto.
[0063] As illustrated in FIG. 2, the touch panel 100 further
includes a substrate 105 and a window 103. The first touch
electrodes 111-1 to 111-m and the second touch electrodes 121-1 to
121-n may be disposed on the substrate 105. The window 103 may be
disposed on the first touch electrodes 111-1 to 111-m and the
second touch electrodes 121-1 to 121-n. In FIG. 2, the first touch
electrodes 111-1 to 111-m and the second touch electrodes 121-1 to
121-n are illustrated to be disposed on a same layer 101, but may
be on different layers, respectively, and the present invention is
not limited thereto.
[0064] The first touch electrodes 111-1 to 111-m are connected to
the first driver/receiver 110, and the second touch electrodes
121-1 to 121-n are connected to the second driver/receiver 120. In
FIG. 1, the first driver/receiver 110 and the second
driver/receiver 120 are separated from each other, but may be
implemented as one module, unit, or chip, and the present invention
is not limited thereto.
[0065] The first driver/receiver 110 may apply a driving signal to
the first touch electrodes 111-1 to 111-m. In addition, the first
driver/receiver 110 may receive a detection signal from the first
touch electrodes 111-1 to 111-m. Similarly, the second
driver/receiver 120 may apply a driving signal to the second touch
electrodes 121-1 to 121-n. In addition, the second driver/receiver
120 may receive a detection signal from the first touch electrodes
121-1 to 121-n. That is, the first driver/receiver 110 and the
second driver/receiver 120 may be a type of transceiver for
transmitting and receiving signals, and each may include a driver
and a receiver.
[0066] The driving signal may include a signal (e.g., a sine wave,
a square wave, etc.) having a frequency corresponding to a resonant
frequency of a stylus pen 20. The resonance frequency of the stylus
pen 20 depends on a design value of a resonant circuit portion 23
of the stylus pen.
[0067] The touch apparatus 10 may be used to detect a touch input
(direct touch or proximity touch) by a touch object. As illustrated
in FIG. 2, the touch input of the stylus pen 20 proximate to the
touch panel 100 may be sensed by the touch apparatus 10.
[0068] The stylus pen 20 may include a conductive tip 21, the
resonant circuit portion 23, a ground 25, and a body 27.
[0069] The conductive tip 21 may be at least partially formed of a
conductive material (e.g., a metal, a conductive rubber, a
conductive fabric, a conductive silicon, etc.), and may be
electrically connected to the resonant circuit portion 23.
[0070] The resonant circuit portion 23, which is an LC resonant
circuit, may resonate with a driving signal applied from at least
one of the first driver/receiver 110 and the second driver/receiver
120 to at least one kind of all electrodes among the first touch
electrodes 111-1 to 111-m and the second touch electrodes 121-1 to
121-n through the conductive tip 21.
[0071] A resonance signal generated when the resonant circuit
portion 23 resonates with the driving signal may be outputted to
the touch panel 100 through the conductive tip 21. The driving
signal caused by the resonance of the resonant circuit portion 23
may be transferred to the conductive tip 21 during a period in
which the driving signal is applied to at least one kind of all
electrodes among the first touch electrodes 111-1 to 111-m and the
second touch electrodes 121-1 to 121-n and during a following
period. The resonant circuit portion 23 may be disposed in the body
27, and may be electrically connected to the ground 25.
[0072] The stylus pen 20 in this manner generates a touch input by
generating a resonance signal in response to a driving signal
applied to at least one of the touch electrodes 111-1 to 111-m and
121-1 to 121-n.
[0073] Capacitance Cx is generated by at least one of the touch
electrodes 111-1 to 111-m and 121-1 to 121-n, and the conductive
tip 21 of the stylus pen 20. The driving signal and the resonance
signal may be respectively transferred to the stylus pen 20 and the
touch panel 100 through the capacitance Cx generated by at least
one of the touch electrodes 111-1 to 111-m and 121-1 to 121-n, and
the conductive tip 21 of the stylus pen 21.
[0074] The touch apparatus 10 may detect a touch by a touch object
(e.g., a user's body (finger, palm, etc.), a passive or active
stylus pen) other than the stylus pen 20 using the above-described
method of generating the resonance signal.
[0075] For example, the touch apparatus 10 detects a touch by a
stylus pen that receives an electrical signal and outputs it as a
magnetic field signal. For example, the touch apparatus 10 may
further include a digitizer. A touch may be detected by detecting
the magnetic field signal that is electromagnetically resonant (or
electromagnetically induced) by the stylus pen by the digitizer.
Alternatively, the touch apparatus 10 detects a touch by a stylus
pen which receives a magnetic field signal and outputs it as a
resonant magnetic field signal. For example, the touch apparatus 10
may further include a coil for applying a current as a driving
signal and the digitizer. The stylus pen resonates with a magnetic
field signal generated by the coil to which the current is applied.
A touch may be detected by detecting the magnetic field signal that
is electromagnetically resonant (or electromagnetically induced) by
the stylus pen by the digitizer.
[0076] The controller 130 may control driving of the touch
apparatus 10, and may output touch coordinate information in
response to a touch detection result of the touch apparatus 10.
[0077] Next, a touch detection method according to an exemplary
embodiment of the present invention will be described with
reference to FIG. 3.
[0078] FIG. 3 schematically illustrates a touch detection method
according to an exemplary embodiment.
[0079] In a first period, the touch apparatus 10 is driven in a
first mode (S10). The first mode is a mode in which a driving
signal for detecting a touch input by a touch object other than the
stylus pen 20 is applied to the touch panel 100.
[0080] For example, in the first mode, the first driver/receiver
110 outputs a driving signal to the first touch electrodes 111-1 to
111-m, and the second driver/receiver 120 receives a detection
signal depending on a touch from the second touch electrodes 121-1
to 121-n.
[0081] The controller 130 may determine whether the detection
signal is a valid touch signal based on whether a signal magnitude
of the detection signal acquired during the first period exceeds a
first threshold, and may obtain touch coordinate information by
using the valid touch signal.
[0082] For example, the controller 130 calculates touch coordinates
by using the detection signal when the signal magnitude of the
detection signal acquired during the first period exceeds the first
threshold. The controller 130 does not calculate touch coordinates
depending on the detection signal having a signal magnitude that is
less than or equal to the first threshold when the signal magnitude
of the detection signal acquired in the first period is less than
or equal to the first threshold. In addition, when the signal
magnitude of the detection signal acquired in the first period
exceeds the first threshold, the controller 130 may calculate a
touch area by using the detection signal. The detection signal
acquired in the first period includes at least one of a first
detection signal caused by a user's body part (a finger, a palm,
etc.), and a second detection signal caused by the stylus pen 20 or
a passive stylus pen. The first threshold may be set such that the
first detection signal is determined to be a valid touch signal and
the second detection signal is filtered.
[0083] During a first subperiod of a second period, the touch
apparatus 10 is driven in a second mode (S12). The second mode is a
mode in which a driving signal for detecting a touch input by the
stylus pen 20 is applied to the touch panel 100. For example, the
first driver/receiver 110 simultaneously applies a driving signal
to all of the first touch electrodes 111-1 to 111-m.
[0084] Although it has been described above that the first
driver/receiver 110 simultaneously applies driving signals to all
of the plurality of first touch electrodes 111-1 to 111-m during
the first subperiod, the second driver/receiver 120 may
simultaneously apply driving signals to all of the plurality of
second touch electrodes 121-1 to 121-n during the second period, or
the first driver/receiver 110 and the second driver/receiver 120
may simultaneously apply driving signals to all of the plurality of
first touch electrodes 111-1 to 111-m and the driving signals to
all of the second touch electrodes 121-1 to 121-n. When the first
driver/receiver 110 and the second driver/receiver 120 provide
driving signals to both the plurality of first touch electrodes
111-1 to 111-m and the plurality of second touch electrodes 121-1
to 121-n, it is assumed that phases of the driving signals applied
to the first touch electrodes 111-1 to 111-m and the driving
signals applied to the second touch electrodes 121-1 to 121-n are
the same, but the present invention is not limited thereto.
[0085] It is assumed that a frequency of the driving signal applied
to the touch panel 100 during the first period is equal to or less
than a frequency of the driving signal applied to the touch panel
100 during the first subperiod.
[0086] During a second subperiod of the second period, the touch
apparatus 10 receives a resonated detection signal based on the
driving signal (S14).
[0087] For example, the resonant circuit portion 23 of the stylus
pen 20 resonates with the drive signal, thereby generates a
resonant signal, which is transferred to the touch panel 100
through the conductive tip 21. Then, the first driver/receiver 110
receives detection signals transferred from the first touch
electrodes 111-1 to 111-m, and the second driver/receiver 120
receives detection signals transferred from the second touch
electrodes 121-1 to 121-n. The first driver/receiver 110 and the
second driver/receiver 120 may process the received detection
signals to transfer them to the controller 130.
[0088] The controller 130 may determine whether the detection
signal is a valid touch signal based on whether a signal magnitude
of the detection signal acquired during the second subperiod
exceeds a second threshold, and may obtain touch coordinate
information related to a point where a touch of the stylus pen 20
occurs by using the valid touch signal.
[0089] For example, the controller 130 calculates touch coordinates
by using the detection signal when a signal magnitude of the
detection signal acquired during a third period exceeds the second
threshold. The controller 130 does not calculate touch coordinates
depending on the detection signal having a signal magnitude that is
less than or equal to the second threshold when the signal
magnitude of the detection signal acquired in the third period is
less than or equal to the second threshold. In addition, when the
signal magnitude of the detection signal acquired in the third
period exceeds the second threshold, the controller 130 may
calculate a touch area by using the detection signal.
[0090] Next, a driving signal applied in the first and second
periods and a resonance signal of the stylus pen 20 will be
described with reference to FIG. 4.
[0091] FIG. 4 illustrates a waveform diagram showing an example of
a driving signal according to the touch detection method of FIG.
3.
[0092] During the first period T1, the first driver/receiver 110
outputs a driving signal to at least one kind of touch electrodes
among the first touch electrodes 111-1 to 111-m and the second
touch electrodes 121-1 to 121-n. When the first driver/receiver 110
outputs a driving signal to the first touch electrodes 111-1 to
111-m, the second driving and receiving 120 may receive detection
signals from the second touch electrodes 121-1 through 121-n. The
controller 130 may obtain touch coordinate information based on a
signal magnitude of the detection signal.
[0093] During the first subperiod T21 in the second period T2, the
first driver/receiver 110 simultaneously applies a driving signal
to the first touch electrodes 111-1 to 111-m, and the second
driver/receiver 120 simultaneously applies a driving signal to the
second touch electrodes 121-1 to 121-n.
[0094] During the first subperiod 21, a frequency of the driving
signal applied to the first touch electrodes 111-1 to 111-m and the
second touch electrodes 121-1 to 121-n correspond to a resonance
frequency of the stylus pen 20. For example, the frequency of the
driving signal outputted to the first touch electrodes 111-1 to
111-m and the second touch electrodes 121-1 to 121-n during the
first subperiod T21 may be a frequency within an offset of 25 kHz
to about 500 kHz. In contrast, during the first period T1, the
frequency of the driving signal outputted to the first touch
electrodes 111-1 to 111-m is set differently from the resonance
frequency of the stylus pen 20. For example, the frequency of the
driving signal outputted to the first touch electrodes 111-1 to
111-m during the first period T1 may be set to about 150 kHz. The
frequency setting of the driving signal is merely an example, and
may be set to a value different from the above.
[0095] During the first subperiod T22 in the second period T2, the
first driver/receiver 110 receives detection signals from the first
touch electrodes 111-1 to 111-m, and the second driver/receiver 120
receives detection signals from the second touch electrodes 121-1
to 121-n.
[0096] Even after application of the driving signal is completed
during the second subperiod T22, a resonance signal outputted by
the resonant circuit portion 23 of the stylus pen 20 may be
received by at least one of the first touch electrodes 111-1 to
111-m and the second touch electrodes 121-1 to 121-n.
[0097] The second period T2 includes a plurality of first
subperiods T21 and second subperiods T22. For example, during the
second period T2, a combination of the first subperiod T21 and the
second subperiod T22 may be repeated eight times.
[0098] Although the second period T2 exists after the first period
T1, the first period T1 may exist after the second period T2, and
time lengths of the first period T1 and the second period T2 may be
changed in various frames, respectively, and the driving method of
the touch apparatus 10 according to the exemplary embodiment is not
limited thereto.
[0099] Next, a detection signal when a touch is inputted between
two adjacent touch electrodes will be described with reference to
FIG. 5 to FIG. 8.
[0100] FIG. 5 partially illustrates a touch panel and a receiver
according to a conventional art, FIG. 6 illustrates a waveform
diagram showing an example of a reception signal received by two
electrodes of the touch panel shown in FIG. 5, FIG. 7 partially
illustrates a touch panel and a driver according to an exemplary
embodiment, and FIG. 8 illustrates a waveform diagram showing an
example of a reception signal received by two electrodes of the
touch panel shown in FIG. 7.
[0101] First, as illustrated in FIG. 5, a first receiver 1100 of
the first driver/receiver 110 includes a plurality of differential
amplifiers 113-1 and 113-2, an ADC unit 115, and a digital signal
processor (DSP) 117. A second receiver 1200 of the second
driver/receiver 120 includes a plurality of differential amplifiers
123-1 and 123-2, an ADC unit 125, and a digital signal processor
(DSP) 127.
[0102] Specifically, the differential amplifiers 113-1 and 113-2
and 123-1 and 123-2, may be implemented as amplifiers each having
two input terminals, a first terminal of which receives one
detection signal and a second terminal of which receives another
detection signal.
[0103] In general, the signal received from the touch electrode not
only receives a desired signal, but also receives noise. This noise
deteriorates the quality of the signal, thereby reducing the
sensitivity of the system, and in the case of display noise on a
display, the noise is introduced into all channels at a similar
magnitude. Therefore, when a difference between the detection
signals received by the two touch electrodes is amplified, noise
components may cancel each other, and only the difference between
the signals may be amplified, thereby obtaining good quality
signals.
[0104] Input terminals of the differential amplifiers 113-1 and
113-2, and 123-1 and 123-2, are connected to two adjacent touch
electrodes, respectively. Specifically, the differential amplifier
113-1 is connected to the first touch electrodes 111-1 and 111-2
adjacent to each other, and the differential amplifier 113-2 is
connected to the first touch electrodes 111-3 and 111-4 adjacent to
each other. The differential amplifier 123-1 is connected to the
second touch electrodes 121-1 and 121-2 adjacent to each other, and
the differential amplifier 123-2 is connected to the second touch
electrodes 121-3 and 121-4 adjacent to each other.
[0105] Each of the differential amplifiers 113-1 and 113-2, and
123-1 and 123-2, may differentially amplify and output two
detection signals transferred from the touch electrodes connected
with the input terminals.
[0106] In FIG. 5, when one point TP between two adjacent touch
electrodes 111-1 and 111-2 is touched, the differential amplifier
113-1 connected to the two touch electrodes 111-1 and 111-2
amplifies a difference between the two detection signals. The
controller 130 determines whether the detection signals from the
two touch electrodes 111-1 and 111-2 are valid touch signals by
using the signal outputted by the differential amplifier 113-1.
However, since the detection signals received from the two touch
electrodes 111-1 and 111-2 are the same in magnitude, or are very
similar, the signal outputted by the differential amplifier 113-1
has a very small magnitude.
[0107] As illustrated in FIG. 6, during the second subperiod T22,
the detection signals R_111-1 and R-111-2 from the two touch
electrodes 111-1 and 111-2 have similar magnitudes and phases.
Therefore, a signal O_113-1 outputted by the differential amplifier
113-1 has a very small signal magnitude .DELTA.Va. Therefore, a
touch input for one point TP is difficult to detect.
[0108] When the differential amplifier 113-1 receives the detection
signals from two adjacent touch electrodes, the detection signals
generated by the touch in a region between the first touch
electrode 111-1 and the first touch electrode 111-2 are not
sufficiently large even if they are differentially amplified by the
differential amplifier 113-1. Therefore, when the differential
amplifier 113-1 is connected with two adjacent touch electrodes,
touch sensitivity is deteriorated.
[0109] As illustrated in FIG. 7, the input terminals of the
respective differential amplifiers 113-1 and 113-2, and 123-1 and
123-2, are connected to two touch electrodes that are spaced apart
from each other by at least one touch electrode. Specifically, the
differential amplifier 113-1 is connected to the first touch
electrodes 111-1 and 111-3 that are spaced apart from the first
touch electrode 111-2, and the differential amplifier 113-2 is
connected to the first touch electrodes 111-2 and 111-4 that are
spaced apart from the first touch electrode 111-3. The differential
amplifier 123-1 is connected to the second touch electrodes 121-1
and 121-3 that are spaced apart from the second touch electrode
121-2, and the differential amplifier 123-2 is connected to the
second touch electrodes 121-2 and 121-4 that are spaced apart from
the second touch electrode 121-2.
[0110] In FIG. 7, when one point TP between two adjacent touch
electrodes 111-1 and 111-2 is touched, the differential amplifier
113-1 connected to the two touch electrodes 111-1 and 111-3
amplifies a difference between the two detection signals. The
controller 130 determines whether the detection signals from the
two touch electrodes 111-1 and 111-3 are valid touch signals by
using the signal outputted by the differential amplifier 113-1.
However, since the signal magnitudes between the detection signals
received from the two touch electrodes 111-1 and 111-3 are
different, the signal outputted by the differential amplifier 113-1
may have a magnitude that is greater than or equal to a
threshold.
[0111] As illustrated in FIG. 8, during the second subperiod T22,
the detection signals R_111-1 and R-111-2 from the two touch
electrodes 111-1 and 111-2 have different magnitudes. Therefore,
the signal O_113-1 outputted by the differential amplifier 113-1
has a signal magnitude .DELTA.Vb that is equal to or greater than
the threshold. That is, since the differential amplifier 113-1
receives the detection signals from the first touch electrode 111-1
and the first touch electrode 111-3 which are spaced apart from
each other by at least one touch electrode, the detection signal
generated by the touch electrode at the touch input position may be
differentially amplified to have a sufficiently large value, and
the touch sensitivity may be improved.
[0112] Next, the first and second driver/receivers 110 and 120 of
the touch apparatus 10 will be described in detail with reference
to FIG. 9 and FIG. 11.
[0113] FIG. 9 illustrates a touch apparatus that operates during
the first period T1 in more detail.
[0114] First, FIG. 9 illustrates a touch apparatus during the first
period. As illustrated, a first driver 1110 of the first
driver/receiver 110 includes a plurality of amplifiers 112-1 to
112-m. The amplifiers 112-1 to 112-m are connected to the first
touch electrodes 111-1 to 111-m to output a first driving
signal.
[0115] A second driver 1200 includes a plurality of amplifiers
123-1 to 123-n, an ADC unit 125, and a digital signal processor
(DSP) 127. The second driver/receiver 1200 may sequentially receive
detection signals of the second touch electrodes 121-1 to 121-n in
units of one second touch electrode. Alternatively, the second
driver/receiver 1200 may simultaneously receive detection signals
from the second touch electrodes 121-1 to 121-n.
[0116] Each of the amplifiers 123-1 to 123-n is connected to a
corresponding second touch electrode of the second touch electrodes
121-1 to 121-n. Specifically, each of the amplifiers 123-1 to 123-n
may be implemented as an amplifier in which one input terminal of
two input terminals is connected to a ground or a DC voltage, and a
detection signal is inputted into the other input terminal. Each of
the amplifiers 123-1 to 123-n amplifies the detection signals
transferred from the second touch electrodes 121-1 to 121-n in
parallel to output them.
[0117] The ADC unit 125 converts an amplified detection signal into
a digital signal. The signal processing unit 127 processes a
plurality of amplified signals converted into digital signals to
transfer them to the controller 130.
[0118] Next, a touch apparatus operating in the first subperiod T21
of the second period T2 is illustrated.
[0119] As illustrated, the amplifiers 112-1 to 112-m of the first
driver 1110 are connected to the first touch electrodes 111-1 to
111-m to output a first driving signal.
[0120] A second driver 1210 also includes a plurality of amplifiers
122-1 to 122-n. The amplifiers 122-1 to 122-n are connected to the
first touch electrodes 121-1 to 121-n to output a third driving
signal.
[0121] Next, FIG. 11 illustrates a touch apparatus operating in the
second subperiod T22 of the second period T2. As illustrated, the
first receiver 1100 includes a plurality of differential amplifiers
113-1 to 113-i, an ADC unit 115, and a digital signal processor
(DSP) 117. The second receiver 1200 includes a plurality of
differential amplifiers 123-1 to 123-j, an ADC unit 125, and a
digital signal processor (DSP) 127.
[0122] The differential amplifiers 113-1 to 113-i and 123-1 to
123-j may be configured by changing the connection of the input
terminals of the amplifiers 123-1 to 123-n. That is, an inequality
i+j n may be satisfied. Specifically, two touch electrodes may be
connected to one amplifier by connecting an input terminal of two
input terminals of the amplifier 123-1 to which the ground or the
DC voltage is connected to the corresponding second touch electrode
121-4 and an input terminal of two input terminals of the amplifier
123-1 to which the ground or the DC voltage is connected to the
corresponding second touch electrode 121-5.
[0123] Input terminals of the respective differential amplifiers
113-1 to 113-i and 123-1 to 123-j are connected to two touch
electrodes that are spaced apart from each other by at least one
touch electrode. Each of the differential amplifiers 113-1 to 113-i
and 123-1 to 123-j may differentially amplify and output two sense
signals transferred from the touch electrode. Each of the
differential amplifiers 113-1 to 113-i and 123-1 to 123-j receives
differential detection signals from two touch electrodes to
differentially amplify them, and thus even when a driving signal is
applied to a plurality of touch electrodes at the same time, it is
not saturated.
[0124] Each of the differential amplifiers 113-1 to 113-i and 123-1
to 123-j may receive detection signals from two touch electrodes
that are spaced apart from each other, rather than two adjacent
touch electrodes. For example, each of the differential amplifiers
113-1 to 113-i and 123-1 to 123-j receives a detection signal from
two touch electrodes spaced apart from each other with one or more
touch electrodes therebetween. In FIG. 11, the differential
amplifier 113-1 receives detection signals from the touch electrode
111-1 and the touch electrode 111-5. When the differential
amplifier 113-1 receives the detection signals from two adjacent
touch electrodes (e.g., the first touch electrode 111-1 and the
first touch electrode 111-2), the detection signals caused by the
touch in a region between the first touch electrode 111-1 and the
first touch electrode 111-2 are not sufficiently large even if they
are differentially amplified by the differential amplifier 113-1.
Therefore, when the differential amplifier 113-1 is connected with
two adjacent touch electrodes, touch sensitivity is deteriorated.
However, since the differential amplifier 113-1 receives the
detection signals from the first touch electrode 111-1 and the
first touch electrode 111-5, the detection signal caused by the
touch electrode at the touch input position may be differentially
amplified to have a sufficiently large value, and the touch
sensitivity may be improved.
[0125] Each of the ADC units 115 and 125 converts the
differentially amplified detection signal into a digital signal.
Each of the signal processing units 117 and 127 processes a
plurality of differential amplified signals converted into digital
signals to transfer them to the controller 130.
[0126] Such a touch detection method will be described together
with reference to FIG. 12 to FIG. 16.
[0127] FIG. 12 illustrates a waveform diagram showing an example of
a driving signal and a reception signal according to the touch
detection method of FIG. 3, and FIG. 13 illustrates a part of a
receiver that outputs the reception signal of FIG. 11.
[0128] In FIG. 12 and FIG. 13, it is assumed that there is a touch
by a finger in a region where the first touch electrodes 111-1 and
111-2 and the second touch electrodes 121-1, 121-2, and 121-3 cross
each other.
[0129] As illustrated in FIG. 12, during the first period T1, first
driving signals D_111-1 to D_111-m are sequentially applied to the
first touch electrodes 111-1 to 111-m. The first driving signals
D_111-1 to D_111-m are pulse signals having an enable level voltage
VE and a disable level voltage VD.
[0130] The second receiver 1200 receives the detection signals
R_121-1 to R_121-n from the second touch electrodes 121-1 to
121-n.
[0131] The first driving signals D_111-1 to D_111-m are driving
signals for detecting a touch input by a touch object other than
the stylus pen 20, and are not limited to the waveform illustrated
in FIG. 12. It is illustrated in FIG. 12 that the first driving
signals D_111-1 to D_111-m are sequentially applied to the first
touch electrodes 111-1 to 111-m, but driving signals having
different frequencies (e.g., frequencies having an orthogonal
relationship with each other) may be simultaneously applied to the
first touch electrodes 111-1 to 111-m. In this case, the second
receiver 1200 may receive detection signals depending on a touch
from the second touch electrodes 121-1 to 121-n, and may separate
the detection signals by the first touch electrodes 111-1 to 111-m
using band pass filters of different frequency bands.
[0132] As illustrated in FIG. 13, the detection signal R_121-1 from
the second touch electrode 121-1 may be amplified and outputted
through the corresponding amplifier 123-1, the detection signal
R_121-2 from the second touch electrode 121-2 may be amplified and
outputted through the corresponding amplifier 123-1, the detection
signal R_121-3 from the second touch electrode 121-3 may be
amplified and outputted through the corresponding amplifier 123-1,
and the detection signal R_121 from the second touch electrode
121-4 may be amplified and outputted through the corresponding
amplifier 123-1. In the detection signals R_121-1, R_121-2, and
R_121-3, a change in signal magnitude caused by a touch occurs as
.DELTA.V0, .DELTA.V1, and .DELTA.V2, respectively.
[0133] The controller 130 may calculate, as touch coordinates, a
point at which the first touch electrodes 111-1 and 111-2 to which
a driving signal is applied when a change in signal magnitude is
generated, and the second touch electrodes 121-1, 121-2 and 121-3
in which a signal magnitude change is generated, cross each
other.
[0134] Next, during the first subperiod T21, the second driving
signals D_111-1 to D_111-m are applied to all of the first touch
electrodes 111-1 to 111-m, and the third driving signal D_121 is
applied to all of the second touch electrodes 121-1 to 121-n.
[0135] The second and third driving signals D_111 and D_121 are
pulse signals having a voltage VE of an enable level and a voltage
VD of a disable level, and having a frequency similar to that of a
resonant frequency of the stylus pen 20.
[0136] During the first subperiod T21, reception of detection
signals from the first touch electrodes 111-1 to 111-m and the
second touch electrodes 121-1 to 121-n is not performed.
[0137] During the second subperiod T22, the first receiver 1100 and
the second receiver 1200 may receive detection signals from both
the first touch electrodes 111-1 to 111-m and the second touch
electrodes 121-1 to 121-n.
[0138] Herein, the second period T2 includes a plurality of first
subperiods T21 and second subperiods T22. For example, during the
second period T2, a combination of the first subperiod T21 and the
second subperiod T22 may be repeated eight times.
[0139] In FIG. 11 and FIG. 13, since the touch by the stylus pen 20
does not occur, no detection signal is received during the second
subperiod T22.
[0140] FIG. 14 illustrates a waveform diagram showing another
example of a driving signal and a reception signal according to the
touch detection method of FIG. 3, and FIG. 15 illustrates a part of
a driver that outputs the reception signal of FIG. 14.
[0141] In FIG. 14 and FIG. 15, it is assumed that there is a touch
by the stylus pen 20 in a region where the first touch electrode
111-2 and the second touch electrode 121-5 cross each other.
[0142] As illustrated in FIG. 14, during the first period T1, first
driving signals D_111-1 to D_111-m are sequentially applied to the
first touch electrodes 111-1 to 111-m. The second receiver 1200
receives the detection signals R_121-1 to R_121-n from the second
touch electrodes 121-1 to 121-n.
[0143] Since the stylus pen 20 is close to the second touch
electrode 121-5, a signal magnitude change value .DELTA.V3 of the
detection signal R_121-5 from the touched second touch electrode
121-5 may be amplified and outputted through the amplifier
123-5.
[0144] Next, during the first subperiod T21 in the second period
T2, the second driving signals D_111-1 to D_111-m are applied to
all of the first touch electrodes 111-1 to 111-m, and the third
driving signal D_121 is applied to all of the second touch
electrodes 121-1 to 121-n. The second and third driving signals
D_111 and D_121 are pulse signals having a voltage VE of an enable
level and a voltage VD of a disable level, and having a frequency
similar to that of a resonant frequency of the stylus pen 20.
[0145] In FIG. 14, it is described that the enable level voltage VE
of the second and third driving signals D_111 and D_121 and the
disable level voltage VD are the same in phase signal, but the
present invention is not limited thereto. During the first
subperiod T21, a magnitude of the pen resonance signal increases
according to a time when the second and third driving signals D_111
and D_121 are applied. The magnitude of the pen resonance signal is
saturated after a certain time elapses.
[0146] During the first subperiod T21, reception of detection
signals from the first touch electrodes 111-1 to 111-m and the
second touch electrodes 121-1 to 121-n is not performed.
[0147] Thereafter, when the first subperiod T21 ends, the first
driver 1110 stops applying the driving signal D_111, and the second
driver 1210 stops applying the driving signal D_121. During the
second subperiod T22 in the second period T2, the driving signals
D_111 and D_121 are not applied to the first touch electrodes 111-1
to 111-m and the second touch electrodes 121-1 to 121-n.
[0148] During the second subperiod T22, the first receiver 1100 and
the second receiver 1200 may receive detection signals from both
the first touch electrodes 111-1 to 111-m and the second touch
electrodes 121-1 to 121-n. The first receiver 1100 and the second
receiver 1200 may receive the pen resonance signal in the second
subperiod T22 to which the driving signals D_111 and D_121 are not
applied as a detection signal.
[0149] As illustrated in FIG. 15, a signal magnitude difference
.DELTA.V4 between the detection signal R_111-2 from the first touch
electrode 111-2 with touch and the detection signal R_111-6 from
the first touch electrode 111-6 without touch may be amplified and
outputted through the differential amplifier 113-2. Similarly, a
signal magnitude difference .DELTA.V5 between the detection signal
R_121-5 from the second touch electrode 121-5 with touch and the
detection signal R_121-1 from the second touch electrode 121-1
without touch may be amplified and outputted through the
differential amplifier 123-1.
[0150] The controller 130 may calculate, as touch coordinates, a
point at which the first touch electrodes 111-1 and 111-2 to which
a driving signal is applied when a difference in signal magnitude
is generated, and the second touch electrodes 121-2 and 121-3 in
which a signal magnitude difference is generated, cross each
other.
[0151] The controller 130 may calculate a touch position on the
touch panel 100 through the detection signal received in the second
subperiod T22.
[0152] In accordance with the touch apparatus 10 according to an
exemplary embodiment, since the differential amplifier 113-1
receives the detection signals from the first touch electrode 111-1
and the first touch electrode 111-3 which are spaced apart from
each other by at least one touch electrode, the detection signal
generated by the touch electrode at the touch input position may be
differentially amplified to have a sufficiently large value, and
the touch sensitivity may be improved.
[0153] In addition, in accordance with the touch apparatus 10
according to an exemplary embodiment, since the detection signal is
received through both the first touch electrodes 111-1 to 111-m and
the second touch electrodes 121-1 to 121-n during the second
subperiod, there is an advantage in that touch coordinates along
two axes intersecting each other may be quickly obtained.
[0154] In addition, in accordance with the touch apparatus 10
according to an exemplary embodiment, the same driving signals
D_111 and D_121 are simultaneously applied to both the first touch
electrodes 111-1 to 111-m and the second touch electrodes 121-1 to
121-n during the first period T1, thereby improving the resonant
signal magnitude of the stylus pen 20 in response thereto.
[0155] In the above description, the detection signal may be
received at least once during the second subperiod by at least one
of the first receiver 1100 and the second receiver 1200. In
addition, a time point at which the detection signal is received
may be at least one time point in the second subperiod T22, but the
present invention is not limited thereto.
[0156] Next, the magnitude of the detection signal received in each
of the first period T1 and the first subperiod T21 will be
described with reference to FIG. 16.
[0157] FIG. 16 illustrates a graph showing magnitudes of the
reception signals of FIGS. 12 and 14. One frame 1 FRAME includes a
first period T1 and a first subperiod T21.
[0158] The first subperiod T21 includes a plurality of first
subperiods T21 and second subperiods T22. When the second subperiod
T22 ends, a first period of the next frame is started.
[0159] During the first period T1, the magnitude difference of the
detection signal by a finger is .DELTA.V1 or .DELTA.V2, which
exceeds a first threshold value Threshold1. During the first period
T1, the magnitude difference of the detection signal by the stylus
pen 20 is .DELTA.V3, which is less than or equal to the first
threshold value Threshold1.
[0160] According to the exemplary embodiment, the controller 130
determines a detection signal having a magnitude difference
exceeding the first threshold value Threshold1 as a valid touch
signal during the first period T1. The first threshold value
Threshold1 may be set such that a first detection signal by a
user's body (a finger, a palm, etc.) is determined as a valid touch
signal, and a second detection signal by the stylus pen 20 or a
passive stylus pen is filtered.
[0161] Accordingly, the controller 130 determines the detection
signal by the finger as a valid touch signal, and calculates touch
coordinates by using the detection signal.
[0162] The controller 130 determines that the detection signal by
the stylus pen 20 is not a valid touch signal, and does not
calculate the touch coordinates.
[0163] During the first subperiod T21, the magnitude difference of
the detection signal generated by the stylus pen 20 is .DELTA.V4 or
.DELTA.V5, which exceeds a second threshold value Threshold2.
[0164] The controller 130 determines a detection signal having a
magnitude difference exceeding the second threshold value
Threshold2 as a valid touch signal during the first subperiod T21.
Therefore, the controller 130 determines the detection signal by
the stylus pen 20 as a valid touch signal, and calculates touch
coordinates by using the detection signal.
[0165] Conventionally, when different types of objects contact the
touch sensor together, the touch coordinates are calculated using
only the detection signal in the first period T1, and thus it is
difficult to accurately calculate the touch position by a touch
object having a small change in signal magnitude.
[0166] According to the exemplary embodiments, the first threshold
value Threshold1 may be set such that a first detection signal by a
user's body (a finger, a palm, etc.) is determined as a valid touch
signal, and a second detection signal by the stylus pen 20 or a
passive stylus pen is filtered. As a result, the touch coordinates
of the touch object having the large change in signal magnitude may
be accurately detected during the first period T1, and the touch
coordinates of the touch object having the small change in signal
magnitude may be accurately detected during the first subperiod
T21. Next, a touch area depending on a touch object will be
described with reference to FIG. 17 and FIG. 18.
[0167] FIG. 17 and FIG. 18 illustrate touch areas of different
objects.
[0168] As illustrated in FIG. 17, a finger 30 touches the touch
panel 100. A plurality of touch electrodes 111-3 to 111-5 and 121-4
to 121-6 may be disposed near an area A1 where a tip of the finger
30 contacts the touch panel 100. An area of the touch area A1 may
be calculated by using detection signals received from the touch
electrodes 111-3 to 111-5 and 121-4 to 121-6.
[0169] As illustrated in FIG. 18, the stylus pen 40 touches the
touch panel 100. One first touch electrode 111-6 and one second
touch electrode 121-6 may be disposed near an area A2 where a tip
of the stylus pen 40 contacts the touch panel 100. Alternatively,
two first touch electrodes and two second touch electrodes may be
disposed near an area A2 where the tip of the stylus pen 40
contacts the touch panel 100. That is, a number of the touch
electrodes disposed in the area A2 where the tip of the stylus pen
40 contacts the touch panel 100 is smaller than that of the touch
electrodes disposed in the area A1 where the finger 30 contacts the
touch panel 100. Therefore, the area of the touch area A2 caused by
the touch of the stylus pen 40 is calculated to be a very small
value compared to the touch area A1 caused by the touch of the
finger 30.
[0170] According to the exemplary embodiments, the touch apparatus
10 may transfer touch data including information related to the
area of the touch area to a host apparatus. In this way, the host
apparatus may identify whether the touch object is the finger 30 or
the stylus pen 40.
[0171] According to the exemplary embodiments, the touch apparatus
10 may determine the touch object depending on the calculated area
of the touch area, and may transfer touch data including
information related to the determined touch object to the host
apparatus.
[0172] This will be described with reference to FIG. 19 and FIG.
20.
[0173] FIG. 19 illustrates a block diagram of a manufacturing
method of a display device according to an exemplary embodiment,
and FIG. 20 illustrates an example of touch data provided to a host
from a touch apparatus.
[0174] Referring to FIG. 19, a host 50 may receive touch data from
the touch controller 102 included in the touch apparatus 10. For
example, the host 50 may be a mobile system-on-chip (APC), an
application processor (AP), a media processor, a microprocessor, a
central processing unit (CPU), or a device similar thereto.
[0175] After one frame ends, the touch apparatus 10 may generate
information related to the touch input during one frame as touch
data to transfer it to the host 50.
[0176] Alternatively, when the first period T1 ends, the touch
apparatus 10 may generate touch information that is inputted during
the first period T1 as touch data to transfer it to the host 50,
and when the first subperiod T21 that is continuous to the first
period T1 ends, it may generate information related to a touch that
is inputted during the first subperiod T21 as touch data to
transfer it to the host 50.
[0177] Referring to FIG. 20, touch data 60 may include a touch
count field 61 and one or more touch entity fields 62 and 63.
[0178] In the touch count field 61, a value indicating a number of
touches that are inputted during one frame period may be written.
For example, when touch coordinates of one finger are calculated
during the first period T1 in one frame period, and when touch
coordinates of one stylus pen are calculated during the first
subperiod T21, a value indicating that two touches are inputted is
written in the touch count field 61.
[0179] The touch entity fields 62 and 63 include fields indicating
information related to each touch input. For example, the touch
entity fields 62 and 63 may include a flag field 620, an X-axis
coordinate field 621, a Y-axis coordinate field 622, a Z-value
field 623, an area field 624, and a touch action field 625.
[0180] A number of the touch entity fields 62 and 63 may be equal
to a value written in the touch count field 61.
[0181] A value representing a touch object may be written in the
flag field 620. For example, a finger, a palm, and a stylus pen may
be filled in the flag field 620 with different values. Values
representing the calculated touch coordinates may be written in the
X-axis coordinate field 621 and the Y-axis coordinate field 622. A
value corresponding to the signal strength of the detection signal
may be written in the Z-value field 623. A value corresponding to
an area of the touched area may be written in the area field
624.
[0182] According to exemplary embodiments, the host apparatus 50
receiving touch data 60 determines that a touch object is the
finger 30 when the touch area is larger than the threshold by using
the value of the area field 624, and determines that the touch
object is the stylus pen 40 when the touch area is less than or
equal to the threshold.
[0183] According to the exemplary embodiments, the host apparatus
50 receiving the touch data 60 may identify whether the touch
object is the finger 30 or the stylus pen 40 by using the value of
the flag field 620.
[0184] While this invention has been described in connection with
what is presently considered to be practical exemplary embodiments,
it is to be understood that the invention is not limited to the
disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims.
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