U.S. patent application number 14/754623 was filed with the patent office on 2015-11-05 for touch sensor with integrated signal bus extensions.
The applicant listed for this patent is Apple Inc.. Invention is credited to Sunggu KANG, John Z. Zhong.
Application Number | 20150317013 14/754623 |
Document ID | / |
Family ID | 48870034 |
Filed Date | 2015-11-05 |
United States Patent
Application |
20150317013 |
Kind Code |
A1 |
KANG; Sunggu ; et
al. |
November 5, 2015 |
TOUCH SENSOR WITH INTEGRATED SIGNAL BUS EXTENSIONS
Abstract
A touch sensor may be formed from a flexible substrate such as a
sheet of polymer. The flexible substrate may have a main
rectangular portion and a protruding portion. Capacitive touch
sensor electrodes may be formed on the upper and lower surfaces of
the flexible substrate. Signal lines may be coupled to the touch
sensor electrodes. The ends of the signal lines may extend onto the
protruding portion. Signal lines may be formed on upper and lower
surfaces of the flexible substrate. The signal lines may be coupled
to circuitry on a printed circuit using a connector that receives
the end of the protruding portion. Ground structures on the
protruding portion may be configured to overlap the signal lines or
may be laterally interposed between upper surface signal lines and
lower surface signal lines.
Inventors: |
KANG; Sunggu; (San Jose,
CA) ; Zhong; John Z.; (Saratoga, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Apple Inc. |
Cupertino |
CA |
US |
|
|
Family ID: |
48870034 |
Appl. No.: |
14/754623 |
Filed: |
June 29, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13363648 |
Feb 1, 2012 |
9083344 |
|
|
14754623 |
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Current U.S.
Class: |
345/174 |
Current CPC
Class: |
H03K 2217/96031
20130101; H05K 1/181 20130101; H05K 7/00 20130101; G06F 2203/04103
20130101; H03K 2217/94094 20130101; H05K 2201/10189 20130101; Y02P
70/50 20151101; G06F 3/0445 20190501; G06F 3/04164 20190501; G06F
3/0446 20190501; H03K 17/9622 20130101; G06F 3/0488 20130101; G06F
2203/04108 20130101; H05K 2201/10128 20130101 |
International
Class: |
G06F 3/044 20060101
G06F003/044 |
Claims
1. A touch sensor panel, comprising: a flexible substrate including
a main portion having a main width and a plurality of capacitive
touch sensor electrodes coupled to a plurality of signal lines
disposed thereon; and one or more extending portions extending from
a common edge of the main portion, each of the extending portions
having an extending portion width narrower than the main width;
wherein the one or more extending portions include first and second
sections, each of the first and second sections having one or more
of the plurality of signal lines formed on only one side of the
extending portion and not on the other side of the extending
portion.
2. The touch sensor panel of claim 1, wherein the flexible
substrate comprises a flexible sheet of polymer, and wherein the
main portion comprises a rectangular main portion having four
edges, one of the four edges being the common edge.
3. The touch sensor panel of claim 1, wherein some of the plurality
of capacitive touch sensor electrodes are formed on a first surface
of the flexible substrate, and wherein some of the plurality of
capacitive touch sensor electrodes are formed on a second surface
of the flexible substrate.
4. The touch sensor panel of claim 3, wherein the first section
includes a first ground structure on the second surface that at
least partially overlaps at least one of the plurality of signal
lines on the first surface, and wherein the second section includes
a second ground structure on the first surface that at least
partially overlaps at least one of the plurality of signal lines on
the second surface.
5. The touch sensor panel of claim 3, wherein the plurality of
capacitive touch sensor electrodes comprise indium tin oxide and
wherein the plurality of signal lines comprise a conductive
material selected from the group consisting of metal and indium tin
oxide.
6. The touch sensor panel of claim 3, wherein the one or more
extending portions further includes a third section that includes
one or more of the plurality of signal lines on the first surface
and a ground structure on the second surface that overlaps at least
some of the plurality of signal lines on the first surface.
7. An electronic device, comprising: a housing; a display mounted
in the housing; and a touch sensor panel that at least partially
overlaps the display, wherein the touch sensor panel includes a
flexible substrate having a main portion including a common edge
with a main width and a plurality of separated extending portions
extending from the common edge and having one or more extending
portion widths less than the main width, and a plurality of signal
lines formed on opposing first and second surfaces of the main
portion and the plurality of separated extending portions; wherein
a first extending portion of the plurality of separated extending
portions includes one or more of the plurality of signal lines
formed only on the first surface and not on the second surface, and
wherein a second extending portion of the plurality of separated
extending portions includes one or more of the plurality of signal
lines formed only on the second surface and not on the first
surface.
8. The electronic device of claim 7, wherein at least one of the
separated extending portions is bent.
9. The electronic device of claim 7, wherein the touch sensor panel
comprises a plurality of capacitive touch sensor electrodes on the
flexible substrate and wherein the plurality of signal lines are
coupled to the plurality of capacitive touch sensor electrodes.
10. The electronic device of claim 7, wherein the touch sensor
panel further comprises a ground structure on the second surface
that at least partially overlaps the one or more signal lines on
the first surface.
11. The electronic device of claim 7, wherein the one or more of
the plurality of signal lines formed only on the first surface are
laterally offset from the one or more of the plurality of signal
lines formed only on the second surface, and wherein the touch
sensor panel further comprises: first ground structures on the
second surface of the first extending portion that at least
partially overlap the one or more of the plurality of signal lines
formed only on the first surface; and second ground structures on
the first surface of the second extending portion that at least
partially overlap the one or more of the plurality of signal lines
formed only on the second surface.
12. The electronic device of claim 7, wherein the first and second
extending portions overlap each other in an overlapping region and
wherein the touch sensor panel further comprises: first ground
structures on the second surface of the first extending portion in
the overlapping region, wherein the first ground structures are
laterally interposed between the one or more of the plurality of
signal lines; second ground structures on the first surface of the
second extending portion in the overlapping region, wherein the
second ground structures are laterally interposed between the one
or more of the plurality of signal lines.
13. The electronic device of claim 9, further comprising: a printed
circuit; at least one integrated circuit mounted on the printed
circuit; and a connector on the printed circuit that receives at
least one of the plurality of separated extending portions and has
metal structures coupled to one or more of the plurality of signal
lines.
14. A touch sensor panel comprising: a flexible polymer sheet
having opposing first and second surfaces, wherein the flexible
polymer sheet includes a main portion having a common edge with a
main width and one or more protruding portions having one or more
protruding portion widths less than the main width, the one or more
protruding portions protruding from the common edge; capacitive
touch sensor electrodes formed on the flexible polymer sheet; and a
plurality of signal lines connected to the capacitive touch sensor
electrodes and extending onto the one or more protruding portions;
wherein the one or more protruding portions include first and
second sections, the first section including one or more of the
plurality of signal lines formed only on the first surface and not
on the second surface, and the second section including one or more
of the plurality of signal lines formed only on the second surface
and not on the first surface; and wherein the first and second
signal lines are non-overlapping.
15. The touch sensor panel of claim 14 wherein the main portion is
rectangular and has four edges including the common edge.
16. The touch sensor panel of claim 14, wherein some of the
capacitive touch sensor electrodes are formed on the first surface
and some of the capacitive touch sensor electrodes are formed on
the second surface, wherein some of the plurality of signal lines
are coupled to the capacitive touch sensor electrodes on the first
surface and some of the plurality of signal lines are coupled to
the capacitive touch sensor electrodes on the second surface.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
patent application Ser. No. 13/363,648, filed Feb. 1, 2012 (U.S.
Patent Application Publication No. 2013/0194759), the contents of
which are incorporated by reference herein in their entirety for
all purposes.
BACKGROUND
[0002] This relates generally to sensors, and more particularly, to
touch sensors for electronic devices.
[0003] Electronic devices such as portable computers and cellular
telephones are often provided with displays. Touch sensitive
displays are often used to provide users with the ability to
interact with a display through touch-based commands. Touch
sensitive displays can be implemented using capacitive touch
sensor. Capacitive touch sensors may also be used in forming
computer track pads and other input devices.
[0004] A capacitive touch sensor may include an array of touch
sensor electrodes. In configurations such as those in which the
touch sensor is being used as part of a display, the touch sensor
electrodes may be formed from pads of transparent conductive
material such as indium tin oxide. When a user brings a finger or
other external object into the vicinity of the touch sensor
electrodes, touch sensor circuitry can detect changes in
capacitance on the touch sensor electrodes. These detected
capacitance changes can be processed to generate touch event data
for controlling an electronic device.
[0005] To satisfy consumer demand for small form factor devices,
capacitive touch sensor arrays are sometimes formed on thin
flexible substrates such as sheets of polyimide. A flexible printed
circuit signal bus formed from a separate strip of polyimide can be
attached to the edge of touch sensor substrate to route signals
from the touch sensor to a logic board within a device.
[0006] The signal lines in the flexible printed circuit bus may be
attached to the capacitive touch sensor substrate using anisotropic
conductive film. Care must be taken not to impose excessive stress
on anisotropic conductive film bonds between the flexible printed
circuit bus and the touch sensor substrate, because excessive
stress may lead to reliability issues. This type of restriction on
the amount of acceptable stress for the anisotropic conductive film
bonds may impose undesired constraints on use of the flexible
printed circuit bus when installing a touch sensor in an electronic
device. For example, the acceptable bend radius for the flexible
printed circuit bus may be limited. There may also be additional
cost and complexity associated with attaching the flexible printed
circuit bus to the touch sensor.
[0007] It would therefore be desirable to be able to provide
improved touch sensors for electronic devices.
SUMMARY
[0008] An electronic device may have a display mounted in a
housing. A touch sensor may be mounted over the display or may be
mounted in other portions of the device.
[0009] The touch sensor may be formed from a flexible substrate
such as a sheet of polymer. The flexible substrate may have a main
rectangular portion and a protruding portion that protrudes from
one or more edges of the main rectangular portion.
[0010] Capacitive touch sensor electrodes and associated signal
lines may be formed on the upper and lower surfaces of the flexible
substrate. The signal lines may be coupled to the touch sensor
electrodes. The signal lines may extend onto the protruding portion
of the flexible substrate. The signal lines on the protruding
portion of the flexible substrate may be coupled to circuitry on a
printed circuit using one or more connectors.
[0011] Ground structures on the protruding portion may be
configured to overlap the signal lines or may be laterally
interposed between upper surface signal lines and lower surface
signal lines.
[0012] Further features of the invention, its nature and various
advantages will be more apparent from the accompanying drawings and
the following detailed description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a cross-sectional side view of an illustrative
electronic device having a touch sensor in accordance with an
embodiment of the present invention.
[0014] FIG. 2 is a top view of an illustrative touch sensor having
integral flexible printed circuit bus structures in accordance with
an embodiment of the present invention.
[0015] FIG. 3 is a top view of an illustrative touch sensor having
integral flexible printed circuit bus structures on protruding tail
portions that are attached to each other using adhesive in
accordance with an embodiment of the present invention.
[0016] FIG. 4 is a cross-sectional side view of a flexible printed
circuit bus structure having signal traces on an upper surface and
a ground structure on an opposing lower surface in accordance with
an embodiment of the present invention.
[0017] FIG. 5 is a cross-sectional side view of a flexible printed
circuit bus structure having signal traces on a lower surface and a
ground structure on an opposing upper surface in accordance with an
embodiment of the present invention.
[0018] FIG. 6 is a cross-sectional side view of a flexible printed
circuit bus structure formed by attaching bus structures of the
type shown in FIG. 4 to bus structures of the type shown in FIG. 5
using adhesive in accordance with an embodiment of the present
invention.
[0019] FIG. 7 is a top view of a touch sensor with an integral
flexible printed circuit bus structure having regions with traces
on an upper surface, regions with traces on a lower surface, and
regions with traces on both the upper and lower surfaces in
accordance with an embodiment of the present invention.
[0020] FIG. 8 is a cross-sectional side view of an illustrative
configuration that may be used for the regions of the flexible
printed circuit bus structure of FIG. 7 that include traces on both
upper and lower surfaces in accordance with an embodiment of the
present invention.
[0021] FIG. 9 is a cross-sectional side view of another
illustrative configuration that may be used for the regions of the
flexible printed circuit bus structure of FIG. 7 that include
traces on both upper and lower surfaces in accordance with an
embodiment of the present invention.
[0022] FIG. 10 is a cross-sectional side view of an illustrative
touch sensor with an integral flexible printed circuit tail section
having traces on its lower surface that is attached to a printed
circuit using a connector in accordance with an embodiment of the
present invention.
[0023] FIG. 11 is a cross-sectional side view of an illustrative
touch sensor with an integral flexible printed circuit tail section
having traces on its upper surface that is attached to a printed
circuit using a connector in accordance with an embodiment of the
present invention.
[0024] FIG. 12 is a cross-sectional side view of an illustrative
touch sensor with an integral flexible printed circuit tail having
traces on its upper and lower surfaces that may be attached to a
printed circuit using a connector in accordance with an embodiment
of the present invention.
[0025] FIG. 13 is a top view of a portion of a touch sensor with an
integral flexible printed circuit bus structure showing
illustrative bend axis locations along which the flexible printed
circuit bus structure may be bent in accordance with an embodiment
of the present invention.
[0026] FIG. 14 is a top view of an illustrative touch sensor
showing how integral flexible printed circuit bus structures may
protrude outwards along one or more sides of a main rectangular
portion of the touch sensor and may reduce signal path in
accordance with an embodiment of the present invention.
[0027] FIG. 15 is a top view of an illustrative touch sensor
showing how integral flexible printed circuit bus structures may
protrude outwards along two different edges of a rectangular touch
sensor substrate in accordance with an embodiment of the present
invention.
DETAILED DESCRIPTION
[0028] Electronic devices such as electronic device 10 of FIG. 1
may be provided with one or more touch sensors such as touch sensor
12.
[0029] As shown in FIG. 1, device 10 may have a housing such as
housing 14. Housing 14 may be formed from metal, glass, ceramic,
plastic, fiber-based composites, other materials, or combinations
of these materials.
[0030] A display such as display 20 may be mounted in housing 14.
Display 20 may be a liquid crystal display, an organic
light-emitting diode display, a plasma display, an electrowetting
display, an electrophoretic display, or a display formed using
other display technologies. Display 20 may be formed from one or
more rigid substrate layers (e.g., one or more glass substrate
layers) and/or one or more flexible substrate layers (e.g., one or
more polymer layers).
[0031] Display cover layer 16 may cover display 20. Display cover
layer 16 may be formed from glass, plastic, or other transparent
material. Touch sensor 12 may be mounted between display 20 and
display cover layer 16 using a layer of adhesive such as adhesive
18. If desired, touch sensor 12 may be mounted in housing 12 of
device 10 using other arrangements. For example, touch sensor 12
may be attached to the upper surface of display structures 20 or
may be incorporated into the layers of material that make up
display structures 20. Touch sensors such as touch sensor 12 may
also be incorporated into non-display components such as track pads
or other input devices.
[0032] The touch sensor elements that form touch sensor 12 may be
based on any suitable touch sensor technology such as acoustic
touch technology, force-sensor-based touch technology, resistive
touch technology, or capacitive touch technology (as examples). In
capacitive touch sensors, capacitive electrodes may be formed from
a conductive material. For example, for use in display applications
in which the touch sensor electrodes are transparent to allow a
user to view an underlying display, the touch sensor electrodes may
be formed from a transparent conductive material such as indium tin
oxide. Configurations in which touch sensor 12 is a capacitive
touch sensor and in which touch sensor electrodes for touch sensor
12 are formed from transparent conductive materials are sometimes
described herein as an example. Other types of arrangements may be
used for touch sensor 12 if desired (e.g., arrangements with
non-capacitive sensors, arrangements with capacitive electrodes
formed from materials other than indium tin oxide, etc.).
[0033] The capacitive electrodes of touch sensor 12 may be formed
on a substrate such as a transparent substrate. For example, the
touch sensor electrodes may be formed on a rectangular clear
flexible plastic substrate such as a sheet of polyimide or other
polymer. As shown in FIG. 1, the substrate for touch sensor 12 may
have an integral portion such as portion 26 that protrudes outward
from the edges of the main portion of the touch sensor substrate.
Portion 26 may be a flexible tail portion or other extending
portion of touch sensor 12 that includes a signal bus for routing
signals between display 12 and control circuitry such as control
circuitry on printed circuit board 22.
[0034] One or more electronic components such as components 24 may
be mounted in housing 14 of device 10. Components 24 may include
integrated circuits, discrete components such as capacitors,
resistors, and inductors, switches, speakers, microphones,
connectors, and other electrical components. Components 24 may be
mounted on one or more printed circuit boards such as printed
circuit 22. Printed circuit 22 may be, for example, a rigid printed
circuit board such as a board formed from fiberglass-filled epoxy
(e.g., FR4) or may be a flexible printed circuit ("flex circuit")
formed from a flexible sheet of polyimide or other flexible
polymer. Components 24 may include surface mount technology (SMT)
parts and other components that are mounted on printed circuit 22
using solder (as an example). The circuits that are mounted on
printed circuit 22 may include, for example, one or more integrated
circuits for controlling the operation of touch sensor 12. As an
example, components 24 may include a touch sensor integrated
circuit that converts raw capacitance data from touch sensor
electrodes on touch sensor 12 into touch event data for processing
by applications and operating system functions running on device
10.
[0035] Protruding flexible tail portion 26 of the touch sensor
substrate may include conductive lines (e.g., metal traces) that
form a signal bus. The signal bus may be used to conveying signals
between touch sensor electrodes that are located on the main
portion of touch sensor 12 that is located under cover layer 16 and
components 24 on printed circuit 22. As shown in FIG. 1, end 28 of
flexible tail portion 26 of touch sensor 12 may be connected to
printed circuit 22 using one or more connectors such as connector
74. If desired, other attachment mechanisms may be used for
connecting signal lines in portion 26 of touch sensor 12 to printed
circuit 22 (e.g., conductive bonds formed from solder, conductive
bonds formed from anisotropic conductive film, etc.). The use of
connectors such as connector 74 to connect portions such as portion
26 of touch sensor 12 to circuitry on printed circuit 22 is merely
illustrative.
[0036] Tail portion 26 of touch sensor 12 may be formed from one or
more extending (protruding) portions of the substrate used to form
touch sensor 12. An illustrative configuration is shown in FIG. 2.
As shown in the example of FIG. 2, touch sensor 12 may have a
substrate such as substrate 32. Substrate 32 may have a main
portion such as main portion 33 with a rectangular outline or other
suitable shape. Protruding portion 26 may be formed from integral
extending portions of substrate 32 that extend outwards from one or
more of the edges of main portion 33.
[0037] Capacitive electrodes such as electrodes 34 and 38 may be
formed on substrate 32. Electrodes 34 and 38 may have any suitable
shapes (e.g., squares, diamonds, elongated rectangles, etc.). In
the illustrative configuration of FIG. 2, electrodes 34 and 38 have
the shape of elongated rectangles (i.e., strips). Electrodes 34
extend horizontally to form rows. Electrodes 38 extend vertically
to form columns. By monitoring capacitance changes associated with
the horizontal and vertical electrodes, touch sensor 12 may be used
to ascertain the location of an external object such as finger 36
during a touch event (i.e., when a user of device 10 brings finger
36 in contact with cover glass 16 or otherwise brings finger 36
into close proximity to sensor 12).
[0038] Conductive lines such as conductive lines 40 may each be
coupled to a respective one of electrodes 34 and may be routed from
main portion 33 (e.g., a rectangular planar portion) of substrate
32 to protruding portion 26. Conductive lines 42 may each be
coupled to a respective one of electrodes 38 and may likewise be
routed from main portion 33 to protruding portion 26. In protruding
portion 26, signal lines such as lines 40 and 42 may run parallel
to each other and may form signal buses (i.e., protruding portion
26 may form an integral flexible printed circuit bus for touch
sensor 12).
[0039] Conductive electrodes 38 and 34 may, if desired, be formed
on the same side of substrate 32. In this type of arrangement, an
intervening dielectric coating layer may be used to prevent
electrodes 38 and 34 from being shorted to each other. In the
illustrative configuration of FIG. 2, electrodes 34 and 38 are
formed on opposing surfaces of substrate 32. In particular,
electrodes 34 and associated signal routing lines 40 have been
formed on the upper surface of substrate 32, whereas electrodes 38
and associated signal routing lines 42 have been formed on the
lower surface of substrate 32.
[0040] Conductive lines 40 and 42 may be formed from conductive
material such as metal (e.g., copper), transparent conductive
material such as indium tin oxide, or other conductive substances.
For example, conductive lines 40 and 42 may be copper lines, indium
tin oxide lines, or lines that include a lower layer of indium tin
oxide and an upper layer of copper (as examples).
[0041] Main portion 33 of substrate 32 may have a rectangular
shape, a shape with curved edges, a shape with straight edges, a
shape with curved and straight edges, or other suitable shapes.
When mounted to a planar support structure such as planar cover
glass 16 or planar display structures 20, main portion 33 may be
maintained in a planar state. If desired, main portion 33 may be
mounted to a curved surface (e.g., a curved cover glass, etc.).
[0042] Protruding structure 26 may extend from one or more edges of
main portion 33. For example, protruding structure 26 may have
three separate tab-shaped (e.g., rectangular) extending portions
that each extend from the lower edge of main portion 33, as shown
in FIG. 2. In this type of arrangement, portion 26 may have one or
more sections (labeled "T" in FIG. 2) that are used to support
lines 40 (i.e., signal lines on the top of substrate 32), and one
or more sections (labeled "B" in FIG. 2) that are used to support
lines 42 (i.e., signal lines on the lower surface of substrate 32).
Lines 40 extend from the upper surface of substrate 32 to the upper
surface of sections T. Within sections T of extended portion 26,
lines 40 generally run parallel to each other and form a signal
bus. Lines 42 extend from the lower surface of substrate 32 to the
lower surface of section B of extended portion 26, where lines 42
form a signal bus.
[0043] In the example of FIG. 2, there is one "B" section and two
"T" sections. This type of arrangement may help minimize the need
for the lines associated with upper electrodes 34 (i.e., lines 40)
from crossing the lines associated with lower electrodes 38 (i.e.,
lines 42). Minimizing crossing of the upper and lower signal lines
in touch sensor 12 may improve touch sensor signal quality by
reducing spurious signals due to unwanted coupling between the
upper and lower lines. There may, in general, be any suitable
number of "T" and "B" sections in extending portion 26. These
sections of portion 26 may extend laterally from the lower edge of
main portion 33, from one or more side edges of main portion 33,
and/or from the top edge of portion 33.
[0044] As shown in FIG. 3, sections T and B may be configured to
overlap. This type of structure may be formed by laminating
multiple polymer sheets together (as an example). With a
configuration of the type shown in FIG. 3, sections T and B do not
overlap in regions 56. In regions 58, portion 26T of sections T
overlaps portion 26B of section B.
[0045] A cross-sectional side view of section T of extending
portion 26 of substrate 32 of FIG. 2 taken along line 50 and viewed
in direction 44 is shown in FIG. 4. As shown in FIG. 4, section T
of extending portion 26 may include signal lines 40 that run along
the upper surface of substrate 32 and an overlapping ground
structure such as ground 60 that runs under the signal lines along
the lower surface of substrate 32. Ground 60 may be formed from
metal (e.g., copper), transparent conductor (e.g., indium tin
oxide), a layered structure having a lower layer of indium tin
oxide and an upper layer of copper or other metal, or other
suitable conductive materials.
[0046] A cross-sectional side view of section B of extending
portion 26 of substrate 32 of FIG. 2 taken along line 46 and viewed
in direction 48 is shown in FIG. 5. As shown in FIG. 5, section B
of extending portion 26 may include signal lines 42 that run along
the lower surface of substrate 32 and an overlapping ground
structure such as ground 62 that runs on top of the signal lines
along the upper surface of substrate 32. Ground 62 may be formed
from metal (e.g., copper), transparent conductor (e.g., indium tin
oxide), a layered structure having a lower layer of indium tin
oxide and an upper layer of copper or other metal, or other
suitable conductive materials.
[0047] FIG. 6 is a cross-sectional side view of region 58 of
extending portion 26 of touch sensor substrate 32 showing how upper
section T may be attached to lower section B using adhesive such as
adhesive 64.
[0048] As shown in the top view of touch sensor 12 in FIG. 7,
extending portion 26 may, if desired, include sections T and B that
merge into a section "T/B" that includes signal lines on both upper
and lower surfaces of substrate 32. Sections T and B may extend
from different portions of the lower edge of main portion 33 of
substrate 32 and may be separated by optional openings such as
openings 66 in substrate 32. In sections T, lines 40 may run in
parallel on the upper surface of substrate 32 whereas ground 60 may
cover some or all of the lower surface of substrate 32. In section
B, lines 42 may run in parallel on the lower surface of substrate
32 whereas ground 62 may cover some or all of the upper surface of
substrate 32. In section T/B of extended portion 26 of substrate
32, lines 42 may be run in parallel along the upper surface of
substrate 32 and lines 42 may run along the lower surface of
substrate 32. To avoid signal interference, it may be desirable to
laterally offset lines 40 and 42 so that they do not overlap each
other.
[0049] FIG. 8 is a cross-sectional side view of an illustrative
section T/B of extended portion 26 of touch sensor substrate 32 of
FIG. 7 taken along line 68 and viewed in direction 70. As shown in
the illustrative configuration of FIG. 8, lines 40 and lines 42 may
be formed on protruding portion 26 of common substrate 32. Lines 40
may run parallel to each other along the upper surface of substrate
32. Lines 42 may run parallel to each other along the lower surface
of substrate 32. To minimize signal interference, lines 40 and
lines 42 may be formed in different areas, so that lines 40 and
lines 42 are laterally offset from each other and do not overlap.
As shown in FIG. 8, for example, lines 40 may be formed on the
right-hand side of section T/B and lines 42 may be formed on the
left-hand side of section T/B.
[0050] Grounding structures may be provided on substrate 32 such as
ground structures 62 and 60. In the illustrative configuration of
FIG. 8, ground structures 62 are formed on the upper surface of
substrate 32 and overlap lines 42, whereas ground structures 60 are
formed on the lower surface of substrate 32 and overlap lines 40.
In the illustrative configuration of FIG. 9, ground structures 62
on the upper surface of substrate 32 are laterally interposed
between lines 40 and 42, but do not overlap lines 42. Similarly,
ground structures 60 on the lower surface of substrate 32 of FIG. 9
are laterally interposed between lines 42 and 40, but do not
overlap lines 40. If desired, other configurations may be used
(e.g., with ground structures 62 that partly overlap lines 42
and/or ground structures 60 that partly overlap lines 40,
etc.).
[0051] The signal lines on extending portion 26 may be coupled to
circuitry on a printed circuit such as printed circuit 22 of FIG.
1. Signal line connections between extended portion 26 of substrate
32 and circuitry in device 10 such as circuitry on printed circuit
22 may be formed using solder, anisotropic conductive film,
connectors, other connection techniques, or combinations of these
arrangements.
[0052] As shown in FIG. 10, for example, section B of extended
portion 26 may be inserted into a connector such as connector 70 on
printed circuit 22. Printed circuit 22 may include conductive paths
(e.g., metal traces) such as path 72. Paths such as paths 72 may be
coupled to electrical components such as component 24 (e.g., using
solder). Extended portion 26 may include section B. Section B may
be bent so that portion 26 may be received in connector 74. Signal
lines 42 may be formed on the lower surface of substrate 32 in
section B.
[0053] Connector 74 may have a connector housing such as connector
housing 76. Metal structures such as metal spring structure 78 may
be formed in housing 76 and may be used in interconnecting lines 42
to paths 72. As shown in FIG. 10, metal structure 78 may have a
spring portion such as spring portion 80 that contacts a respective
one of lines 42. Portion 82 of metal structure 78 may be connected
to path 72 using solder 84 (as an example). Ground structures on
extending portion 26 (not shown in FIG. 10) may be coupled to paths
on printed circuit 22 using a separate metal structure. FIG. 11
shows how section T of extended portion may be coupled to printed
circuit 22 using a connector such as connector 74. When section T
of substrate 32 is inserted in connector 74, signal lines such as
signal line 40 of FIG. 11 may be coupled to path 72 via metal
structure 78 and solder 84. Ground structures on extending portion
26 (not shown in FIG. 11) may be coupled to printed circuit 22
using a separate metal structure.
[0054] If desired, connector 74 may include multiple metal
structures such as metal structures 78A and 78B of FIG. 12. With
this type of configuration, connector 74 may be used to form both
upper and lower signal lines connections for a portion of extending
portion 26 (e.g., section T/B such as sections T/B of FIGS. 8 and
9). As shown in FIG. 12, signal lines such as single line 40 may be
coupled to paths 72 on printed circuit 22 using metal structures
such as structure 78B and signal lines such as signal line 42 may
be coupled to paths 72 on printed circuit 22 using metal structures
such as structure 78A. Ground structures on extending portion 26
(not shown in FIG. 12) may likewise be coupled printed circuit 22
using metal structures in connector 74.
[0055] One or more sections of extended portion 26 of touch sensor
substrate 32 may be connected to printed circuit 22 using
connectors such as connector 74 of FIG. 10, connector 74 of FIG.
11, and/or connector 74 of FIG. 12 (e.g., one or more "B" sections,
one or more "T" sections and/or one or more "T/B" sections).
[0056] FIG. 13 is a top view of an illustrative portion of
substrate 32 of touch sensor 12 showing illustrative locations for
a bend axis along which substrate 32 may be bent when installed
within housing 14. As shown in FIG. 13, substrate 32 may be bent
along a bend axis such as bend axis 90 or a bend axis such as bend
axis 88 to allow protruding portion 26 to be bent (see, e.g., FIGS.
1, 10, 11, and 12). If desired, substrate 32 may be bent along a
bend axis such as bend axis 86 that intersects substrate 32 in main
portion 33 (i.e., main portion 33 of substrate 32 may be bent in
addition to or instead of bending protruding portion 26 of
substrate 32). Configurations for touch sensor 12 in which
substrate 32 is not bent may also be used.
[0057] Protruding portion 26 of substrate 32 may be formed along
any suitable edge of main portion 33 of substrate 32. In the
example of FIG. 14, protruding portion 26 has two sections ("T")
formed as protruding extensions of the left and right edges of main
portion 33 of substrate 32 on which parallel upper signal lines 40
are used to form signal buses. Protruding portion 26 also has two
sections ("B") formed as protruding extensions of upper and lower
edges of main portion 33 of substrate 32 on which parallel lower
signal lines 42 are used to form signal buses.
[0058] By arranging sections of protruding portion 26 on each of
the edges of substrate 32 as shown in FIG. 14, the length of signal
lines such as signal lines 40 and 42 that are used in conveying
signals between the capacitive touch sensor electrodes and
protruding portion 26 can be minimized. Because the length of
signal lines 40 and 42 can be reduced, less area is consumed by
signal lines. As a result, the width W around the periphery of main
portion 33 that is consumed by signal traces can be minimized and
the inactive portion of touch sensor 12 can be minimized.
[0059] In the example of FIG. 14, protruding portion 26 protrudes
from each of the four edges of rectangular main portion 33 of
substrate 32. FIG. 15 is a top view of touch sensor 12 in an
illustrative configuration in which protruding portion 26 extends
from two of the four edges of main portion 33. Configurations in
which different numbers of sections protrude from main portion 33
may be used (e.g., configurations with more than one section
protruding from each side of main portion 33, configurations with
extending sections on all four edge, on three edges, on two edges,
or on one edge of portion 33, etc.).
[0060] The foregoing is merely illustrative of the principles of
this invention and various modifications can be made by those
skilled in the art without departing from the scope and spirit of
the invention.
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