U.S. patent application number 10/635748 was filed with the patent office on 2005-02-10 for capacitive sensing device for use in a keypad assembly.
Invention is credited to Bolender, Robert J., Rubenson, Benjamin C..
Application Number | 20050030048 10/635748 |
Document ID | / |
Family ID | 34116300 |
Filed Date | 2005-02-10 |
United States Patent
Application |
20050030048 |
Kind Code |
A1 |
Bolender, Robert J. ; et
al. |
February 10, 2005 |
Capacitive sensing device for use in a keypad assembly
Abstract
One embodiment in accordance with the present invention includes
a capacitive sensing device for use in a keypad assembly of an
electronic system. The capacitive sensing device includes a
substantially transparent single sheet capacitive sensor. The
substantially transparent single sheet capacitive sensor is
configured to be disposed within the keypad assembly without
requiring the formation of key post holes therethrough.
Additionally, the substantially transparent single sheet capacitive
sensor has a flexibility which enables desired tactile response
during use of keys of the keypad assembly.
Inventors: |
Bolender, Robert J.; (Davis,
CA) ; Rubenson, Benjamin C.; (San Jose, CA) |
Correspondence
Address: |
WAGNER, MURABITO & HAO LLP
Third Floor
Two North Market Street
San Jose
CA
95113
US
|
Family ID: |
34116300 |
Appl. No.: |
10/635748 |
Filed: |
August 5, 2003 |
Current U.S.
Class: |
324/661 ;
345/174 |
Current CPC
Class: |
H01H 2209/082 20130101;
H01H 2225/002 20130101; H01H 13/702 20130101; H01H 2221/07
20130101; G06F 3/0443 20190501; H01H 2239/006 20130101; G06F
2203/04111 20130101; G06F 3/0202 20130101; H01H 13/807 20130101;
H01H 2227/004 20130101; G06F 3/0446 20190501 |
Class at
Publication: |
324/661 ;
345/174 |
International
Class: |
G01R 027/26; G09G
005/00 |
Claims
What is claimed is:
1. A capacitive sensing device for use in a keypad assembly of an
electronic system, said capacitive sensing device comprising: a
substantially transparent single sheet capacitive sensor, said
substantially transparent single sheet capacitive sensor configured
to be disposed within said keypad assembly without requiring the
formation of key post holes therethrough; and said substantially
transparent single sheet capacitive sensor having a flexibility
which enables desired tactile response during use of keys of said
keypad assembly.
2. The capacitive sensing device of claim 1, wherein said
substantially transparent single sheet capacitive sensor comprises:
a substantially transparent substrate; a first pattern of
conductive sensors disposed above said substantially transparent
substrate, said first pattern of conductive sensors comprised of a
substantially transparent material and disposed within a sensing
region; a second pattern of conductive sensors disposed above said
substantially transparent substrate, said second pattern of
conductive sensors comprised of said substantially transparent
material and disposed within said sensing region, said
substantially transparent material of said first pattern of
conductive sensors and said substantially transparent material of
said second pattern of conductive sensors disposed in a common
single layer above said substantially transparent substrate; and a
plurality of conductive bridges disposed to electrically couple
portions of said second pattern of conductive sensors.
3. The capacitive sensing device of claim 2, wherein said plurality
of conductive bridges is opaque.
4. The capacitive sensing device of claim 2, wherein said
substantially transparent material comprises indium tin oxide.
5. The capacitive sensing device of claim 2, wherein said first
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said first pattern of conductive sensors.
6. The capacitive sensing device of claim 5, wherein said portion
of said substantially opaque conductive material further comprises
openings extending therethrough such that light is able to pass
through said openings of said substantially opaque conductive
material.
7. The capacitive sensing device of claim 5, wherein said first
pattern of conductive sensors is disposed to minimize capacitive
interference with at least one of said plurality of conductive
bridges.
8. The capacitive sensing device of claim 5, wherein said portion
of said substantially opaque conductive material overlies at least
a portion of said substantially transparent material of said first
pattern of conductive sensors.
9. The capacitive sensing device of claim 5, wherein said
substantially opaque conductive material comprises conductive
ink.
10. The capacitive sensing device of claim 2, wherein said second
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said second pattern of conductive sensors.
11. The capacitive sensing device of claim 10, wherein said portion
of said substantially opaque conductive material overlies at least
a portion of said substantially transparent material of said second
pattern of conductive sensors.
12. The capacitive sensing device of claim 10, wherein said portion
of said substantially opaque conductive material of said second
pattern of conductive sensors further comprises openings extending
therethrough such that light is able to pass through said openings
of said substantially opaque conductive material.
13. The capacitive sensing device of claim 2, wherein said
plurality of conductive bridges is selectively disposed to lessen
visual interference with indicia of said keys of said keypad
assembly.
14. A capacitive sensing device comprising: a substantially
transparent substrate; a first pattern of conductive sensors
disposed above said substantially transparent substrate, said first
pattern of conductive sensors comprised of a substantially
transparent material, said first pattern of conductive sensors
disposed within a sensing region; a second pattern of conductive
sensors disposed above said substantially transparent substrate,
said second pattern of conductive sensors comprised of said
substantially transparent material, said second pattern of
conductive sensors formed within said sensing region, said
substantially transparent material of said first pattern of
conductive sensors and said substantially transparent material of
said second pattern of conductive sensors disposed in a common
single layer above said substantially transparent substrate; and a
plurality of conductive bridges disposed to electrically couple
portions of said second pattern of conductive sensors.
15. The capacitive sensing device of claim 14, wherein said
plurality of conductive bridges is opaque.
16. The capacitive sensing device of claim 14, wherein said first
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said first pattern of conductive sensors.
17. The capacitive sensing device of claim 16, wherein said portion
of said substantially opaque conductive material further comprises
openings extending therethrough to allow light to pass through said
openings of said substantially opaque conductive material.
18. The capacitive sensing device of claim 16, wherein said first
pattern of conductive sensors is disposed to minimize capacitive
interference with at least one of said plurality of conductive
bridges.
19. The capacitive sensing device of claim 16, wherein said portion
of said substantially opaque conductive material overlies at least
a portion of said substantially transparent material of said first
pattern of conductive sensors.
20. The capacitive sensing device of claim 16, wherein said
substantially opaque conductive material comprises conductive
ink.
21. The capacitive sensing device of claim 14, wherein said
substantially transparent material comprises indium tin oxide.
22. The capacitive sensing device of claim 14, wherein said second
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said second pattern of conductive sensors.
23. The capacitive sensing device of claim 22, wherein said portion
of said substantially opaque conductive material of said second
pattern of conductive sensors overlies at least a portion of said
substantially transparent material of said second pattern of
conductive sensors.
24. The capacitive sensing device of claim 22, wherein said portion
of said substantially opaque conductive material of said second
pattern of conductive sensors further comprises openings extending
therethrough such that light is able to pass through said openings
of said substantially opaque conductive material.
25. The capacitive sensing device of claim 14, wherein said
plurality of conductive bridges is selectively disposed to lessen
visual interference with indicia of keys of a keypad assembly.
26. The capacitive sensing device of claim 14, wherein said
capacitive sensing device has a flexibility which enables desired
tactile response during use of keys of a keypad when said
capacitive sensing device is disposed in a keypad assembly.
27. A capacitive sensing device comprising: a substantially
transparent substrate; a first pattern of conductive sensors
disposed above said substantially transparent substrate, said first
pattern of conductive sensors comprised of a substantially
transparent material and disposed within a sensing region of said
capacitive sensing device; a second pattern of conductive sensors
disposed above said substantially transparent substrate, said
second pattern of conductive sensors comprised of said
substantially transparent material and disposed within said sensing
region, said substantially transparent material of said first
pattern of conductive sensors and said substantially transparent
material of said second pattern of conductive sensors disposed in a
common single layer above said substantially transparent substrate;
and a plurality of conductive bridges disposed to electrically
couple portions of said second pattern of conductive sensors,
wherein said first pattern of conductive sensors further comprises
at least a portion comprised of a substantially opaque conductive
material electrically coupled to said substantially transparent
material of said first pattern of conductive sensors.
28. The capacitive sensing device of claim 27, wherein said
plurality of conductive bridges is opaque.
29. The capacitive sensing device of claim 27, wherein said portion
of said substantially opaque conductive material further comprises
openings extending therethrough such that light is able to pass
through said openings of said substantially opaque conductive
material.
30. The capacitive sensing device of claim 27, wherein said first
pattern of conductive sensors is disposed to minimize capacitive
interference with at least one of said plurality of conductive
bridges.
31. The capacitive sensing device of claim 27, wherein said portion
of said substantially opaque conductive material overlies at least
a portion of said substantially transparent material of said first
pattern of conductive sensors.
32. The capacitive sensing device of claim 27, wherein said second
pattern of conductive sensors further comprises: at least a portion
comprised of said substantially opaque conductive material
electrically coupled to said substantially transparent material of
said second pattern of conductive sensors.
33. The capacitive sensing device of claim 32, wherein said portion
of said substantially opaque conductive material of said second
pattern of conductive sensors overlies at least a portion of said
substantially transparent material of said second pattern of
conductive sensors.
34. The capacitive sensing device of claim 32, wherein said portion
of said substantially opaque conductive material of said second
pattern of conductive sensors further comprises openings extending
therethrough such that light is able to pass through said openings
of said substantially opaque conductive material.
35. The capacitive sensing device of claim 27, wherein said
substantially transparent material comprises indium tin oxide.
36. The capacitive sensing device of claim 27, wherein said
substantially opaque conductive material comprises conductive
ink.
37. The capacitive sensing device of claim 27, wherein said
plurality of conductive bridges is selectively disposed to lessen
visual interference with indicia of keys of a keypad, when said
capacitive sensing device is disposed in a keypad assembly.
38. The capacitive sensing device of claim 27, wherein said
capacitive sensing device has a flexibility which enables desired
tactile response during use of keys of a keypad when said
capacitive sensing device is disposed in a keypad assembly.
39. An integrated keypad assembly for an electronic device
comprising: a keypad structure; a keymat that is deformable to
actuate a switch sensor; and a capacitive sensor coupled to said
keymat and said key pad structure and not disposed beneath said
keymat.
40. The integrated keypad assembly of claim 39, wherein said
capacitive sensor comprises sensors having at least a portion
thereof disposed around an area to be lighted.
41. The integrated keypad assembly of claim 39, wherein said
capacitive sensor is disposed between said keymat and said key pad
structure.
42. The integrated keypad assembly of claim 39, wherein said keypad
structure is integral with said keymat.
43. The integrated keypad assembly of claim 39, wherein said
capacitive sensor is integrated within said keymat.
44. The integrated keypad assembly of claim 39, wherein said
capacitive sensor comprises a single sheet capacitive sensor.
45. The integrated keypad assembly of claim 44, wherein said single
sheet capacitive sensor comprises: a substantially transparent
substrate; a first pattern of conductive sensors disposed above
said substantially transparent substrate, said first pattern of
conductive sensors comprised of a substantially transparent
material and disposed within a sensing region of said capacitive
sensor; a second pattern of conductive sensors disposed above said
substantially transparent substrate, said second pattern of
conductive sensors comprised of said substantially transparent
material and disposed within said sensing region, said
substantially transparent material of said first pattern of
conductive sensors and said substantially transparent material of
said second pattern of conductive sensors disposed in a common
single layer above said substantially transparent substrate; and a
plurality of conductive bridges disposed to electrically couple
portions of said second pattern of conductive sensors.
46. The integrated keypad assembly of claim 45, wherein said
plurality of conductive bridges is opaque.
47. The integrated keypad assembly of claim 45, wherein said first
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said first pattern of conductive sensors.
48. The integrated keypad assembly of claim 47, wherein said
portion of said substantially opaque conductive material further
comprises openings extending therethrough such that light is able
to pass therethrough.
49. The integrated keypad assembly of claim 47, wherein said first
pattern of conductive sensors is disposed to minimize capacitive
interference with at least one of said plurality of conductive
bridges.
50. The integrated keypad assembly of claim 47, wherein said
portion of said substantially opaque conductive material overlies
at least a portion of said substantially transparent material of
said first pattern of conductive sensors.
51. The integrated keypad assembly of claim 47, wherein said
portion of said substantially opaque conductive material comprises
conductive ink.
52. The integrated keypad assembly of claim 45, wherein said second
pattern of conductive sensors further comprises: at least a portion
comprised of a substantially opaque conductive material
electrically coupled to said substantially transparent material of
said second pattern of conductive sensors.
53. The integrated keypad assembly of claim 52, wherein said
portion of said substantially opaque conductive material of said
second pattern of conductive sensors overlies at least a portion of
said substantially transparent material of said second pattern of
conductive sensors.
54. The integrated keypad assembly of claim 52, wherein said
portion of said substantially opaque conductive material of said
second pattern of conductive sensors further comprises openings
extending therethrough such that light is able to pass through said
openings of said substantially opaque conductive material.
55. The integrated keypad assembly of claim 45, wherein said
substantially transparent material comprises indium tin oxide.
56. The integrated keypad assembly of claim 45, wherein said
plurality of conductive bridges is selectively disposed to minimize
visual interference with indicia of keys of said key pad
structure.
57. The integrated keypad assembly of claim 45, wherein said single
sheet capacitive sensor has a flexibility which enables desired
tactile response during use of keys of said key pad structure when
said single sheet capacitive sensor is disposed in said keypad
assembly.
58. A method of forming a capacitive sensing device, said method
comprising: disposing a first pattern of conductive sensors above
said substantially transparent substrate within a sensing region,
said first pattern of conductive sensors comprised of a
substantially transparent material; disposing a second pattern of
conductive sensors above said substantially transparent substrate
within said sensing region, said second pattern of conductive
sensors comprised of said substantially transparent material, said
substantially transparent material of said first pattern of
conductive sensors and said substantially transparent material of
said second pattern of conductive sensors disposed in a common
single layer above said substantially transparent substrate; and
disposing a plurality of conductive bridges to electrically couple
portions of said second pattern of conductive sensors.
59. The method as described in claim 58, wherein said plurality of
conductive bridges is formed of opaque material.
60. The method as described in claim 58, wherein disposing said
first pattern of conductive sensors further comprises: disposing at
least a portion comprised of a substantially opaque conductive
material electrically coupled to said substantially transparent
material of said first pattern of conductive sensors.
61. The method as described in claim 60, wherein said portion of
said substantially opaque conductive material further comprises
openings extending therethrough such that light is able to pass
through said openings of said substantially opaque conductive
material.
62. The method as described in claim 60, wherein said first pattern
of conductive sensors is disposed to minimize capacitive
interference with at least one of said plurality of conductive
bridges.
63. The method as described in claim 60, wherein said portion of
said substantially opaque conductive material overlies at least a
portion of said substantially transparent material of said first
pattern of conductive sensors.
64. The method as described in claim 60, wherein disposing said
second pattern of conductive sensors further comprises: disposing
at least a portion comprised of a substantially opaque conductive
material electrically coupled to said substantially transparent
material of said second pattern of conductive sensors.
65. The method as described in claim 64, wherein said portion of
said substantially opaque conductive material of said second
pattern of conductive sensors further comprises openings extending
therethrough such that light is able to pass through said openings
of said substantially opaque conductive material.
66. The method as described in claim 64, wherein said portion of
said substantially opaque conductive material of said second
pattern of conductive sensors overlies at least a portion of said
substantially transparent material of said second pattern of
conductive sensors.
67. The method as described in claim 58, wherein said substantially
transparent material is formed of indium tin oxide.
68. The method as described in claim 58, wherein said plurality of
conductive bridges is selectively disposed to lessen visual
interference with indicia of keys of a keypad assembly.
Description
BACKGROUND
[0001] Currently there are at least two different techniques that a
user of a mobile telephone can utilize in order to input text
messages. The first technique is to utilize the numeric input
buttons of the mobile phone to input characters, which can be slow
and tedious considering that some characters and techniques involve
several key depressions per character. A second technique is for
the mobile phone to be enabled with a capacitive sensor and
character recognition abilities such that its user is able to
gesture or "write" with his or her finger over its buttons (without
depressing the buttons) in order to input alphanumeric characters.
This provides a quicker way for entering text into a mobile phone.
Additionally, gestures can also be used to navigate through the
mobile phone operating system and/or menus. However, there are
disadvantages to the conventional techniques for fabricating the
capacitive sensors associated with the finger gesture input.
[0002] For example, a conventional technique is described in PCT
publication WO 02/100074 (the U.S. relative is published as US
2003/0025679) in which the capacitive sensor of a mobile phone
includes holes to allow keypad posts to pass through in order to
activate switches associated with depressed keys. One of the
disadvantages of this conventional technique is that it involves a
lot of compensation in the sensing circuitry of the capacitive
sensor to accommodate the irregular sensor design associated with
routing around the holes. As such, this type of capacitive sensor
can require increased development effort, time, and expense to
adapt to different electronic devices, since the compensation
usually has to be customized for each hole layout, and reconfigured
when the key post holes are rearranged.
[0003] The present invention may address one or more of the above
issues.
SUMMARY
[0004] One embodiment in accordance with the present invention
includes a capacitive sensing device for use in a keypad assembly
of an electronic system. The capacitive sensing device includes a
substantially transparent single sheet capacitive sensor. The
substantially transparent single sheet capacitive sensor is
configured to be disposed within the keypad assembly without
requiring the formation of key post holes therethrough.
Additionally, the substantially transparent single sheet capacitive
sensor has a flexibility which enables desired tactile response
during use of keys of the keypad assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is a diagram of an exemplary mobile telephone that
can be implemented to include one or more embodiments of the
present invention.
[0006] FIG. 2 is a diagram of an exemplary keypad assembly in
accordance with an embodiment of the present invention.
[0007] FIG. 3A is a diagram of an intermediate step in constructing
an exemplary sensor that includes first and second sensor patterns
in accordance with an embodiment of the present invention for a
capacitive sensing device.
[0008] FIG. 3B is a diagram of an exemplary sensor pattern that
includes conductive bridges in accordance with an embodiment of the
present invention for a capacitive sensing device.
[0009] FIG. 4 is a diagram of an exemplary capacitive sensing
device that illustrates selective disposing of substantially opaque
conductive material in accordance with an embodiment of the present
invention.
[0010] FIG. 5 is a side section view of an exemplary capacitive
sensing device in accordance with an embodiment of the present
invention.
[0011] FIG. 6 is a side section view of an exemplary capacitive
sensing device in accordance with an embodiment of the present
invention.
[0012] FIG. 7A is a diagram of an intermediate step in constructing
an exemplary sensor that includes first and second sensor patterns
in accordance with an embodiment of the present invention for a
capacitive sensing device.
[0013] FIG. 7B is a diagram of is an exemplary sensor pattern that
includes conductive bridges in accordance with an embodiment of the
present invention for a capacitive sensing device.
[0014] FIG. 8 is a diagram of an opaque conductive ink bridge in
accordance with an embodiment of the present invention.
[0015] FIG. 9 is a diagram of an exemplary capacitive sensing
device that illustrates selective disposing of substantially opaque
conductive material in accordance with an embodiment of the present
invention.
[0016] FIG. 10 is a diagram illustrating the flexibility of a
capacitive sensing device in accordance with an embodiment of the
present invention.
[0017] FIG. 11 is a side sectional view of a keymat that includes a
capacitive sensing device in accordance with an embodiment of the
present invention.
[0018] FIG. 12 is a flowchart of operations performed in accordance
with an embodiment of the present invention for fabricating a
capacitive sensing device.
[0019] The drawings referred to in this description should not be
understood as being drawn to scale.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] Reference will now be made in detail to embodiments of the
invention, examples of which are illustrated in the accompanying
drawings. While the invention will be described in conjunction with
embodiments, it will be understood that they are not intended to
limit the invention to these embodiments. On the contrary, the
invention is intended to cover alternatives, modifications and
equivalents, which may be included within the spirit and scope of
the invention as defined by the appended claims. Furthermore, in
the following detailed description of the present invention,
numerous specific details are set forth in order to provide a
thorough understanding of the present invention. However, it will
be obvious to one of ordinary skill in the art that the present
invention may be practiced without these specific details. In other
instances, well known methods, procedures, components, and circuits
have not been described in detail as not to unnecessarily obscure
aspects of the present invention.
[0021] FIG. 1 is a diagram of an exemplary mobile telephone 100
that can be implemented to include one or more embodiments in
accordance with the present invention. Specifically, a capacitive
sensor (not shown) can be integrally disposed within a keypad
region 106 of mobile phone 100 thereby enabling both conventional
use of keys 108 of the keypad region 106 having tactile "clicking"
feedback while also enabling the capture of pointing and gesturing
input when a user slides his or her finger over the surface of the
keypad region 106 with or without actually depressing the keys 108.
For example, if a user moved his or her finger over keypad region
106 to form the letter "b", the capacitive sensor would detect this
motion and its character recognition circuitry would identify the
motion and subsequently the letter "b" can be presented on a
display 104 of mobile phone 100. In this manner, a user of mobile
phone 100 can enter alphanumeric text (or commands or other inputs)
more easily with his or her finger via the capacitive sensing
device than by utilizing keys 108 of keypad 106.
[0022] It is noted that, keys 108 of mobile phone 100 can be
lighted from behind. As such, the capacitive sensor can be
implemented such that it is substantially transparent in regions
beneath the keys 108 in order to allow the light to pass from
behind the capacitive sensor to light the tops of keys 108. In this
manner, the lighting of the keys 108 is not significantly adversely
affected by the inclusion of the capacitive sensing device that is
part of keypad 106.
[0023] FIG. 2 is a diagram of an exemplary keypad assembly 200 in
accordance with an embodiment of the present invention.
Specifically, keypad assembly 200 includes a capacitive sensor 208
that can be a thin and flexible sensor that utilizes substantially
transparent components. Within one embodiment, capacitive sensor
208 can include a single sheet capacitive sensor that includes a
single layer of substantially transparent conductive material,
e.g., indium tin oxide (ITO), and an extra layer of substantially
opaque conductive material (e.g., silver ink, carbon ink, a mixture
of silver and carbon inks, etc.) that protects the substantially
transparent conductive material against cracking during manufacture
and/or repetitive use. Since the substantially opaque conductive
material application is also a redundant electrical path, it can be
selectively disposed where desired. For example, the substantially
opaque conductive material could be masked around certain features
in the sensing region of the capacitive sensor 208 to allow
illumination to pass directly through capacitive sensor 208,
thereby allowing keys 204 of keypad structure 206 to be illuminated
to enable visibility of keys 204 in low light. The single sheet
capacitive sensor 208 can also include a substantially transparent
substrate, or the various patterns of the single sheet captive
sensor 208 can be disposed on an existing component of the keypad
assembly 200.
[0024] The keypad assembly 200 for an electronic device (e.g., 100)
includes keypad structure 206, a keymat 210 that is deformable to
actuate switch sensors 214 via key posts 212, and capacitive sensor
208 that is coupled to the keymat 210 and the keypad structure 206.
In this manner, when a user finger 202 exerts a downward force on
one of keys 204, that key 204 is depressed (as shown) which in turn
causes the deformation of capacitive sensor 208 along with keymat
210 which results in the corresponding key post 212 actuating one
or more switch sensors 214. It is noted that capacitive sensor 208
is not disposed beneath the keymat 210 such that keypad post holes
do not have to be formed within capacitive sensor 208, since such
holes would complicate the sensing circuit (not shown) utilized to
interpret signals received from capacitive sensor 208.
[0025] In one embodiment, capacitive sensing device 208 can be
bonded to the top of the keymat 210 and the keypad structure 206
can be bonded to capacitive sensing device 208. It is noted that
keypad structure 206 could be many separate discrete keys that can
be disposed on capacitive sensing device 208 or disposed on some
intermediate member (or component) that is disposed on capacitive
sensing device 208.
[0026] Within FIG. 2, capacitive sensor 208 can be integrated into
the keymat 210 which in one embodiment can be implemented with some
type of rubber material. The keys 204 of keypad structure 206 can
be rigid plastic buttons which include both clear and opaque
regions (e.g., painted on the outside with holes in the paint) to
let any back lighting through for illumination. It is noted that
the indicia of keys 204 can look darkened when there's no light
behind them and they can also glow when the back lighting is
activated such as in response to a user activating one of buttons
204 or a status change of the electronic device (e.g., 100). It is
pointed out that capacitive sensor 208 can be flexible and thin
enough such that it does not inhibit the tactile response
associated with buttons 204. Instead, capacitive sensor 208 enables
the desired tactile response of the keys 204 which may include a
responsive click or snap or less resistant responses. It is noted
that the keypad assembly 200 is one integral unit.
[0027] It is understood that capacitive sensor 208 includes a
sensing region which can include where the buttons 204 are located
on a electronic device or system (e.g., keypad region 106).
However, the sensing region of capacitive sensor 208 may be any
shape, may be smaller than keypad region 106, and/or may extend
outside of where the buttons 204 are into areas that can be covered
up by the housing of the electronic device (e.g., 100).
[0028] It is noted that a single sheet capacitive sensor can
include a single substrate that has two or more conductive sensing
patterns disposed thereon in a common layer that can be utilized
for, but not limited to, 2-dimensional capacitive sensing.
[0029] FIG. 3A is a diagram of an intermediate step in constructing
an exemplary capacitive sensor 300A that includes a first
capacitive sensor pattern 302 and a second capacitive sensor
pattern 304 in accordance with an embodiment of the present
invention for a capacitive sensing device. For example, capacitive
sensor pattern 302 includes electrically coupled horizontal
capacitive sensor traces while capacitive sensor pattern 304
includes the as yet electrically uncoupled vertical sensor
traces.
[0030] It is noted that capacitive sensor patterns 302 and 304 each
includes a layer of substantially transparent conductive material
(not shown) along with a layer of substantially opaque conductive
material (shown). There are a wide variety of ways in accordance
with the present embodiment to fabricate capacitive sensor patterns
302 and 304. For example, in one embodiment a sputtering process
can be used to coat one side of a substantially transparent
flexible substrate 301 with a layer of substantially transparent
conductive material (e.g., ITO). The substantially transparent
conductive material can then be selectively etched away from the
surface of the substantially transparent flexible substrate 301,
revealing an intended "diamond" patterns 302 and 304 which can be
used for a capacitive sensing process. Alternatively, the
substantially transparent material can be applied in any manner to
create the intended diamond patterns 302 and 304. It is noted that
patterns 302 and 304 may include any shapes and are not limited to
the "diamond" patterns or the horizontal and vertical layout shown.
After the etching process of the substantially transparent
conductive material, a first layer of substantially opaque
conductive material is deposited on top of the substantially
transparent conductive material in the desired areas. Within
capacitive sensor 300A, the substantially transparent conductive
material and the substantially opaque conductive material are shown
having a substantial one-to-one correspondence and alignment which
is why the substantially transparent conductive material is not
shown.
[0031] Furthermore, it is noted that in various embodiments of the
present invention, the first and second conductive sensor patterns
are comprised of the same type of substantially transparent
conductive material. It is further noted that in various
embodiments of the present invention, the first and second
conductive sensor patterns are comprised of different types of
substantially transparent conductive materials. Additionally, it is
noted that in various embodiments of the present invention, the
first and second conductive sensor patterns are comprised of the
same type of substantially opaque conductive material. It is
further noted that in various embodiments of the present invention,
the first and second conductive sensor patterns are comprised of
different types of substantially opaque conductive materials.
[0032] Within FIG. 3A, capacitive sensor pattern 302 includes
diamond shapes 318, 320, 322, 324, 326 and 328 which can be
disposed on a substantially transparent flexible substrate 301 as
described herein. The diamonds shapes 318, 320 and 322 of sensor
pattern 302 have been disposed such that they are each electrically
coupled together while diamonds shapes 324, 326 and 328 have been
disposed such that they are each electrically coupled together. As
such, the components of capacitive sensor pattern 302 could be
utilized if coupled to capacitive sensing circuitry (not
shown).
[0033] Alternatively, capacitive sensor pattern 304 includes
isolated diamond shapes 306, 308, 310, 312, 314 and 316 which can
be disposed on the substantially transparent flexible substrate 301
as described herein. The diamond shapes 306, 308, 310, 312, 314 and
316 are electrically isolated and are therefore not yet useful as
input to capacitive sensing circuitry. However, it is pointed out
that the substantially transparent conductive material of the
diamond shapes of capacitive sensor patterns 302 and 304 exist with
a single layer which is advantageous for fabricating a capacitive
sensing device that is thin and flexible.
[0034] Within FIG. 3A, it is noted that the substantially
transparent flexible substrate 301 of the present embodiment may be
implemented in a wide variety of ways. For example, the
substantially transparent flexible substrate 301 can be implemented
with, but is not limited to, Polyethylene Terephthalate (PET).
Additionally, the substantially transparent flexible substrate 301
can have a diverse range of thickness which provide a desired
amount of flexibility. For example, the substantially transparent
flexible substrate 301 can have a thickness of, but is not limited
to, roughly 0.07 millimeters (mm). It is noted that substrate 301
may be implemented such that one or more portions of it are not
substantially transparent (e.g., opaque markings, and the like).
Additionally, the layer of substantially transparent conductive
material of both capacitive sensor patterns 302 and 304 can be
implemented with diverse materials such as, but not limited to,
indium tin oxide (ITO) or any other substantially transparent
conductive material. Moreover, the layer of substantially opaque
conductive material can be implemented in a wide variety of ways in
accordance with the present embodiment. For example, the
substantially opaque conductive material can be implemented as, but
not limited to, conductive ink (e.g., silver ink, carbon ink,
mixture of silver and carbon inks, and the like).
[0035] FIG. 3B is a diagram of an exemplary capacitive sensor 300B
that includes conductive bridges in accordance with an embodiment
of the present invention for a capacitive sensing device.
Specifically, capacitive sensor 300B illustrates one embodiment of
electrically coupling isolated diamonds 306, 308, 310, 312, 314 and
316 of capacitive sensor pattern 304 during a fabrication process
of a capacitive sensing device.
[0036] After the operation associated with FIG. 3A have occurred as
described herein, an insulator 350 can then be disposed in areas
where conductive bridges (e.g., 352 and 354) of sensor pattern 304
will cross the sensor traces of sensor pattern 302 to facilitate
electrically coupling of diamonds 306, 308, 310, 312, 314 and 316.
For example, insulator 350 can be disposed between diamonds 310 and
308 of sensor pattern 304 and also between diamonds 308 and 306.
Furthermore, insulator 350 can be disposed between diamonds 312 and
314 of sensor pattern 304 and also between diamonds 316 and
314.
[0037] Within FIG. 3B, a substantially opaque conductive material
is next disposed to create conductive bridges (e.g., 352 and 354)
that electrically couple diamonds 306, 308, and 310 together and
diamonds 312, 314 and 316 together of sensor pattern 304 and does
not electrically couple to sensor pattern 302. Specifically, the
substantially opaque conductive material is disposed to create a
conductive bridge 352 which electrically couples diamonds 306 with
308 of sensor pattern 304. Additionally, the substantially opaque
conductive material is disposed to create a conductive bridge 354
which electrically couples diamonds 314 with 316. It is appreciated
that diamonds 308 with 310 are also electrically coupled by a
conductive bridge similar to bridge 354 while diamonds 314 with 312
are electrically coupled by a conductive bridge similar to bridge
352. In this manner, diamonds 306, 308 and 310 of sensor pattern
304 are electrically coupled while diamonds 312, 314 and 316 are
electrically coupled.
[0038] In this manner, a single layer of substantially transparent
conductive material can be utilized in order to fabricate a
two-dimensional capacitive sensing device. It is noted that by
including the layer of substantially opaque conductive material
over the substantially transparent conductive material, the
substantially transparent conductive material is protected from
damage during manufacture and/or repetitive use of the capacitive
sensing device. Additionally, the substantially opaque conductive
material can also provide electrical redundancy for the
substantially transparent conductive material if the substantially
transparent conductive material fails. Therefore, a more reliable
and thinner capacitive sensor device can be fabricated.
[0039] It is noted that a substantially transparent insulator can
be disposed over capacitive sensor 300B in order to provide a layer
of protection for capacitive sensor patterns 302 and 304 along with
the conductive bridges (e.g., 352 and 354).
[0040] Within FIG. 3B, insulator 350 can be implemented in a wide
variety of ways in accordance with the present embodiment. For
example, insulator 350 can be implemented as, but is not limited
to, a substantially transparent material, a substantially opaque
material, an opaque material, and/or a printed dielectric material.
Additionally, the substantially opaque conductive material utilized
to create the conductive bridges (e.g., 352 and 354) can be
implemented in diverse ways in accordance with the present
embodiment. For example, the substantially opaque conductive
material can be implemented as, but not limited to, conductive ink
(e.g., silver ink, carbon ink, mixture of silver and carbon inks,
and the like). It is noted that conductive bridges (e.g., 352 and
354) can be implemented in diverse ways in accordance with the
present embodiment. For example, conductive bridges (e.g., 352 and
354) can be implemented as, but is not limited to, a substantially
transparent conductive material, a substantially opaque conductive
material, and/or an opaque conductive material.
[0041] It is understood that the substantially opaque conductive
material, substantially transparent conductive material, conductive
bridges, and/or insulators described herein can be disposed by
utilizing, but not limited to, one or more deposition processes
such as a screen printing process, one or more lithographical
processes such as an etching process, a combination of deposition
and lithographical processes, and the like.
[0042] FIG. 4 is a diagram of an exemplary capacitive sensing
device 400 that illustrates selective disposing of substantially
opaque conductive material in accordance with an embodiment of the
present invention. It is noted that capacitive sensing device 400
can be fabricated in a manner similar to capacitive sensor patterns
300A and 300B of FIGS. 3A and 3B, respectively, as described
herein. The solid lines of capacitive sensing device 400 represent
the substantially opaque conductive material while the dashed lines
represent the underlying substantially transparent conductive
material within an "illumination" opening 402 of capacitive sensing
device 400. In this manner, light is able to pass through opening
402 of capacitive sensing device 400 in order to illuminate one or
more keys (e.g., 204) of a keypad (e.g., 206) associated with an
electronic device (e.g., 100) while still providing capacitive
sensing capabilities within opening 402 via the existing
substantially transparent conductive material. It is understood
that the underlying substantially transparent conductive material
extends beneath the substantially opaque conductive material.
[0043] Within capacitive sensing device 400, the substantially
opaque conductive material of shapes 308a, 320a, 314a and 326a have
been selectively disposed in order to create opening 402.
Additionally, substantially opaque conductive material shape 324a
has been selectively disposed such that it minimizes capacitive
interference to conductive bridge 352a. In this manner, one or more
patterns of substantially opaque conductive material can be
tailored in order to minimize capacitive interference with one or
more conductive bridges (e.g., 352a and/or 354). It should be
understood for purpose of the present application the term
"minimize capacitive interference" is intended to refer to
disposing the conductive bridges in an orientation and location for
reducing capacitive coupling between the conductive bridges and one
or more proximate conductive sensor patterns.
[0044] Within FIG. 4, it is noted that the capacitive sensor
patterns 302a and 304a of capacitive sensing device 400 operate in
manner similar to capacitive sensor patterns 302 and 304 of FIGS.
3A and 3B, described herein.
[0045] FIG. 5 is a side section view of an exemplary capacitive
sensing device 500 wherein a substantially opaque conductive
material 504 is electrically coupled to at least a second portion
of a substantially transparent conductive material 502 within a
capacitive sensor pattern that includes conductive sensors in
accordance with an embodiment of the present invention.
Specifically, it is pointed out that within capacitive sensing
device 500, the substantially opaque conductive material 504 and
the substantially transparent material 502 are substantially within
the same layer as they both are disposed above a substantially
transparent substrate 506. In this manner, the combination of the
substantially transparent material 502 and the substantially opaque
conductive material 504 are able to create one or more capacitive
sensor traces of a capacitive sensor pattern that operates in
manner similar to capacitive sensor patterns 208, 300A, 300B and/or
400.
[0046] It is noted that a finger (e.g., 202) of a user could be on
either side of capacitive sensing device 500 when it is in used. As
such, capacitive sensing device 500 could be oriented such that
substrate 506 is located above substantially transparent conductive
material 502 and substantially opaque conductive material 504 or
vice-versa. Hence, it is understood that when it is mentioned that
something is "above" something else, it is typically in reference
to the orientation of the Figures.
[0047] It is noted that a capacitive sensor device (e.g., 500) that
operates in a manner similar to capacitive sensor device 400 can be
fabricated such that the light openings (e.g., 402) are created
with substantially transparent conductive material 502 while the
remainder of capacitive sensor device 500 is created with
substantially opaque conductive material 504. In this fashion, the
substantially opaque conductive material 504 would not be located
above the substantially transparent conductive material 502, but
instead would be situated within substantially the same layer or
plane as illustrated within capacitive sensor device 500 of FIG. 5.
In this manner, the substantially opaque conductive material 504
and the substantially transparent conductive material 502 would
substantially abut each other.
[0048] Within FIG. 5, it is noted that the substantially
transparent flexible substrate 506 of the present embodiment may be
implemented in a wide variety of ways. For example, the
substantially transparent flexible substrate 506 can be implemented
with, but is not limited to, PET. Additionally, the substantially
transparent flexible substrate 506 can have a diverse range of
thickness which provide a desired amount of flexibility. For
example, the substantially transparent flexible substrate 506 can
have a thickness of, but is not limited to, roughly 0.07 mm.
Additionally, the substantially transparent conductive material 502
can be implemented in diverse ways such as, but not limited to, ITO
or any other substantially transparent conductive material.
Furthermore, the substantially opaque conductive material 504 can
be implemented in a wide variety of ways in accordance with the
present embodiment. For example, the substantially opaque
conductive material 504 can be implemented as, but not limited to,
conductive ink (e.g., silver ink, carbon ink, mixture of silver and
carbon inks, and the like).
[0049] FIG. 6 is a side section view of an exemplary capacitive
sensing device 600 wherein a substantially opaque conductive
material 504a overlies a pattern of substantially transparent
conductive sensors 502a in accordance with an embodiment of the
present invention. Specifically, a first portion of the
substantially opaque conductive material 504a overlies at least a
portion of a pattern of conductive sensors that include
substantially transparent conductive material 502a. It is
understood that within capacitive sensing device 600, the
substantially opaque conductive material 504a overlies (or lies
above) the substantially transparent material 502a. In this manner,
the combination of the substantially transparent material 502a and
the substantially opaque conductive material 504a of capacitive
sensing device 600 have a similar structure as capacitive sensor
patterns 300A, 300B and/or 400. As such, capacitive sensing device
600 operates in a manner similar to capacitive sensor patterns
300A, 300B and/or 400, as described herein.
[0050] Within capacitive sensing device 600, the substantially
transparent material 502a is disposed above the substantially
transparent flexible substrate 506 while the substantially opaque
conductive material 504a is disposed above the substantially
transparent material 502a.
[0051] Within FIG. 6, it is noted that the substantially
transparent flexible substrate 506 of the present embodiment may be
implemented in a wide variety of ways. For example, the
substantially transparent flexible substrate 506 can be implemented
with, but is not limited to, PET. Additionally, the substantially
transparent flexible substrate 506 can have a diverse range of
thickness which provide a desired amount of flexibility. For
example, the substantially transparent flexible substrate 506 can
have a thickness of, but is not limited to, roughly 0.07 mm.
Furthermore, the substantially transparent conductive material 502a
can be implemented in diverse ways such as, but not limited to, ITO
or any other substantially transparent conductive material.
Moreover, the substantially opaque conductive material 504a can be
implemented in a wide variety of ways in accordance with the
present embodiment. For example, the substantially opaque
conductive material 504a can be implemented as, but not limited to,
conductive ink (e.g., silver ink, carbon ink, mixture of silver and
carbon inks, and the like).
[0052] FIG. 7A is a diagram of an intermediate step in constructing
an exemplary sensor 700A that includes a first capacitive sensor
pattern 302b and a second capacitive sensor pattern 304b in
accordance with an embodiment of the present invention for a
capacitive sensing device. It is noted that capacitive sensor 700A
can be fabricated in a manner similar to capacitive sensor 300A of
FIG. 3A, described herein. However, it is noted that the
substantially opaque conductive material of capacitive sensor 700A
has been selectively disposed above the substantially transparent
conductive material similar to a lattice design that includes
openings (e.g., 702). In this manner, a greater amount of light is
able to pass through openings 702 of capacitive sensing 700A in
order to more fully illuminate one or more keys (e.g., 204) of a
keypad (e.g., 206) associated with an electronic device (e.g.,
100).
[0053] It is noted that the openings 702 of capacitive sensor
patterns 302b and 304b are disposed such that the sensing ability
of capacitive sensing device 700A is unaffected. It is understood
that the substantially opaque conductive material of the present
embodiment can be disposed by utilizing, but is not limited to, a
screen printing process, lithographical process, and the like.
Furthermore, the substantially opaque conductive material of other
embodiment described herein can also be disposed by utilizing, but
is not limited to, a screen printing process, lithographical
process, and the like.
[0054] Within FIG. 7A, it is noted that the substantially
transparent flexible substrate 301 of the present embodiment may be
implemented in a wide variety of ways. For example, the
substantially transparent flexible substrate 301 can be implemented
with, but is not limited to, PET. Additionally, the layer of
substantially transparent conductive material of both capacitive
sensor patterns 302 and 304 can be implemented in diverse ways such
as, but not limited to, ITO or any other substantially transparent
conductive material. Furthermore, the layer of substantially opaque
conductive material can be implemented in a wide variety of ways in
accordance with the present embodiment. For example, the
substantially opaque conductive material can be implemented as, but
not limited to, conductive ink (e.g., silver ink, carbon ink,
mixture of silver and carbon inks, and the like).
[0055] FIG. 7B is a diagram of an exemplary capacitive sensor 700B
that includes conductive bridges (e.g., 352b and 354b) in
accordance with an embodiment of the present invention for a
capacitive sensing device. Specifically, capacitive sensor 700B
illustrates one embodiment of electrically coupling isolated
diamonds 306b, 308b, 310b, 312b, 314b and 316b of capacitive sensor
pattern 304b during a fabrication process of a capacitive sensing
device. It is noted that capacitive sensor 700B can be fabricated
in a manner similar to capacitive sensor 300B of FIG. 3B, described
herein. However, the conductive bridges (e.g., 352b and 354b) can
be selectively disposed in order to electrically couple the lattice
design of the substantially opaque conductive material of isolated
diamonds 306b, 308b, 310b, 312b, 314b and 316b. As part of
fabricating one or more conductive bridges (e.g., 352b and 354b),
it can be desirable to utilize a minimum overlap area to provide
sufficient electrical coupling between adjacent diamonds (e.g.,
314b and 316b).
[0056] When fabrication of capacitive sensor 700B has been
completed, an increased amount of light can pass through openings
702 of capacitive sensor 700B as compared to capacitive sensor 300B
(FIG. 3B) thereby more fully illuminating one or more keys (e.g.,
204) of a keypad (e.g., 206) associated with an electronic device
(e.g., 100).
[0057] It is noted that a substantially transparent insulator can
be disposed over capacitive sensor 700B in order to provide a layer
of protection to capacitive sensor patterns 302b and 304b along
with the conductive bridges (e.g., 352b and 354b).
[0058] Within FIG. 7B, insulator 350a can be implemented in a wide
variety of ways in accordance with the present embodiment. For
example, insulator 350a can be implemented as, but is not limited
to, a substantially transparent material, a substantially opaque
material, an opaque material, and/or a printed dielectric material.
Furthermore, the substantially opaque conductive material utilized
to create the conductive bridges (e.g., 352b and 354b) can be
implemented in diverse ways in accordance with the present
embodiment. For example, the substantially opaque conductive
material can be implemented as, but not limited to, conductive ink
(e.g., silver ink, carbon ink, mixture of silver and carbon inks,
and the like).
[0059] FIG. 8 is a top view diagram of a substantially opaque
conductive material bridge (e.g., 354c) in accordance with an
embodiment of the present invention that is routed to minimize
visual interference with indicia (e.g., 802, 804 and 806) of a key
(e.g., 204) of an electronic device (e.g., 100). It is noted that
conductive bridges (e.g., 354c, 354b, 354a, 352b, 352a, 352, and
354) can each be fabricated as desired having, but not limited to,
any length, width, shape, and/or routing path. As such, conductive
bridge 354c of system 800 has been fabricated such that it is
routed so that its visual inference with indicia 802, 804 and 806
is minimized while electrically coupling two or more diamonds
(e.g., 314b and 316b), not shown. It should be understood for
purpose of the present application the term "minimize visual
interference with indicia" is intended to refer to disposing the
conductive bridges in an orientation and location for lessening
visual interference with proximate indicia while providing
electrical coupling. In this manner, a user of an electronic device
(e.g., 100) is able to easily read its keys 204 when they are
illuminated from behind.
[0060] FIG. 9 is a diagram of selectively disposing an exemplary
capacitive sensing device 900 that illustrates selective disposing
of substantially opaque conductive material in accordance with an
embodiment of the present invention. It is noted that capacitive
sensing device 900 can be fabricated in a manner similar to
capacitive sensor patterns 700A and 700B of FIGS. 7A and 7B,
respectively, as described herein. The solid lines of capacitive
sensing device 900 represent the substantially opaque conductive
material while the dashed lines represent the underlying
substantially transparent conductive material within an
"illumination" opening 402a of capacitive sensing device 900. In
this manner, light is able to pass through opening 402a of
capacitive sensing device 900 in order to illuminate one or more
function keys (e.g., 204) of a keypad (e.g., 206) associated with
an electronic device (e.g., 100) while still providing capacitive
sensing capabilities within opening 402a via the existing
substantially transparent conductive material. It is noted that the
underlying substantially transparent conductive material extends
beneath the substantially opaque conductive material and under
openings 902.
[0061] Within capacitive sensing device 900, the substantially
opaque conductive material of shapes 308d, 320d, 314d and 326d have
been selectively disposed in order to create opening 402a along
with a lattice of openings 902. Additionally, substantially opaque
conductive material shape 324d has been selectively disposed such
that it does not provide capacitive interference to conductive
bridge 352d which electrically couples substantially opaque
conductive material shapes 308d and 310d. In this manner, one or
more patterns of substantially opaque conductive material can be
tailored in order to minimize capacitive interference with one or
more conductive bridges (e.g., 352d and/or 354d). It should be
understood for purpose of the present application the term
"minimize capacitive interference" is intended to refer to
disposing the conductive bridges in an orientation and location for
reducing capacitive coupling between the conductive bridges and one
or more proximate conductive sensor patterns.
[0062] Within FIG. 9, it is noted that the capacitive sensor
patterns 302d and 304d of capacitive sensing device 900 operate in
manner similar to capacitive sensor patterns 302b and 304b of FIGS.
7A and 7B, described herein.
[0063] FIG. 10 is a diagram illustrating a flexibility comparison
1000 of a conventional capacitive sensing device 1002 and a
capacitive sensing device 208 in accordance with an embodiment of
the present invention. It is noted that capacitive sensing device
208 can be fabricated in any manner similar to that described
herein. As such, capacitive sensing device 208 results in a thinner
sensing device that has more flexibility thereby enabling the
desired tactile response during use of keys of a keypad assembly.
Specifically, when finger 202 exerts a downward force on capacitive
sensing device 208, it flexes or bends more easily and further than
the conventional capacitive sensor device 1002 when the same amount
of downward force is exerted on it by finger 202. Therefore,
capacitive sensing device 208 can be more desirable when
implemented as part of a keypad assembly (e.g., 200).
[0064] FIG. 11 is a side sectional view of an integrated keypad
assembly in accordance with an embodiment of the present invention
in which an integrated capacitive sensing device is integral to the
keymat. Within keymat assembly 1100, which includes capacitive
sensing device 1104, keys 1108 are formed as part of keymat portion
1102 which can be formed of a rubber material. It is noted that
capacitive sensor device 1104 has been integrated within the rubber
material of keymat assembly 1100. Specifically, keymat assembly
1100 includes a first keymat portion 1102 of rubber and a second
keymat portion 1106 of rubber. As such, the capacitive sensor
device 1104 is disposed between and within rubber portions 1102 and
1106. It is understood that keymat assembly 1100 operates in a
manner similar to keypad assembly 202 of FIG. 2, described
herein.
[0065] FIG. 12 is a flowchart of operations performed in accordance
with an embodiment of the present invention for fabricating a
capacitive sensing device. Although specific operations are
disclosed in flowchart 1200, such operations are exemplary. That
is, the present embodiment is well suited to performing various
other operations or variations of the operations recited in FIG.
12.
[0066] At operation 1202, a first pattern of conductive sensors is
disposed above a substantially transparent substrate within a
sensing region. The first pattern of conductive sensors has at
least a portion thereof that includes a substantially transparent
conductive material. It is noted that the disposing of the first
pattern of conductive sensors at operation 1202 can also include
disposing at least a first portion comprised of substantially
opaque conductive material (e.g., conductive ink) that is
electrically coupled to at least a second portion of the
substantially transparent material (e.g., ITO) of the first pattern
of conductive sensors. It is understood that the sensing region
will be the area proximate to of the capacitive sensing device for
which the capacitive sensing device is designed to actively
"capture" pointing and/or gesturing inputs of a finger of a user
when it is in proximity to the capacitive sensing device.
Furthermore, the disposing of the first pattern of conductive
sensors at operation 1202 can also include the first portion of the
substantially opaque conductive material including openings formed
therethrough such that light is able to pass through the openings
of the substantially opaque conductive material. In one embodiment,
the first portion of substantially opaque conductive material
overlies at least a portion of the first pattern of conductive
sensors.
[0067] The substantially transparent substrate can be implemented
in diverse ways in accordance with the present embodiment. For
example, the substantially transparent substrate can be implemented
as, but is not limited to, a substantially transparent plastic
substrate such as PET. Additionally, the substantially transparent
conductive material can be implemented in a wide variety of ways in
accordance with the present embodiment. For example, the
substantially transparent conductive material can be implemented
as, but is not limited to, indium tin oxide (ITO) or any other
substantially transparent conductive material. Furthermore, the
substantially opaque conductive material can be implemented in a
diverse ways in accordance with the present embodiment. For
example, the substantially opaque conductive material can be
implemented as, but is not limited to, conductive ink, silver ink,
carbon ink, a combination of silver and carbon inks, or any other
substantially opaque conductive material.
[0068] At operation 1204 of FIG. 12, a second pattern of conductive
sensors is disposed above the substantially transparent substrate
within the sensing region. The second pattern of conductive sensors
can also include, but is not limited to, the substantially
transparent material. It is noted that the first pattern of
conductive sensors and the second pattern of conductive sensors can
be disposed in a common single layer above the substantially
transparent substrate. In one embodiment, the disposing of the
second pattern of conductive sensors can also include disposing at
least a first portion comprised of substantially opaque conductive
material that is electrically coupled to at least a second portion
of the substantially transparent material of the second pattern of
conductive sensors. In another embodiment, the first portion of
substantially opaque conductive material of the second pattern of
conductive sensors includes openings formed therethrough such that
light is able to pass through the openings of the substantially
opaque conductive material. Alternatively, the first portion of
substantially opaque conductive material of the second pattern of
conductive sensors overlies at least a portion of the second
pattern of conductive sensors.
[0069] It is noted that operations 1202 and 1204 can occur
concurrently or they can occur sequentially.
[0070] At operation 1205, a plurality of insulators is disposed in
areas where conductive bridges will be disposed (at operation 1206)
to cross sensor traces of the first pattern of conductive sensors
to facilitate electrically coupling of portions of the second
pattern of conductive sensors. It is noted that the plurality of
insulators can be implemented of a wide variety of materials in
accordance with the present embodiment. For example, the plurality
of insulators can be implemented in any manner described herein,
but are not limited to such.
[0071] At operation 1206, a plurality of conductive bridges is
disposed to electrically couple portions of the second pattern of
conductive sensors. It is noted that the plurality of conductive
bridges can be implemented of a wide variety of materials in
accordance with the present embodiment. For example, the plurality
of conductive bridges can be implemented using, but is not limited
to, an opaque conductive material and/or a substantially
transparent conductive material. In one embodiment, the disposing
of the plurality of conductive bridges is selectively disposed to
lessen visual interference with indicia of keys of a keypad
assembly.
[0072] In one embodiment of flowchart 1200, the first pattern of
conductive sensors can be disposed to minimize capacitive
interference with at least one of the plurality of conductive
bridges.
[0073] The foregoing descriptions of specific embodiments of the
present invention have been presented for purposes of illustration
and description. They are not intended to be exhaustive or to limit
the invention to the precise forms disclosed, and obviously many
modifications and variations are possible in light of the above
teaching. The embodiments were chosen and described in order to
best explain the principles of the invention and its practical
application, to thereby enable others skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated. It
is intended that the scope of the invention be defined by the
claims appended hereto and their equivalents.
* * * * *