U.S. patent application number 12/259182 was filed with the patent office on 2009-04-30 for multiple-sensor-electrode capacitive button.
Invention is credited to Izhak Baharav, Tracy Scott Dattalo, John M Feland, III, John C Fravel, Joesph K Reynolds.
Application Number | 20090107737 12/259182 |
Document ID | / |
Family ID | 40581369 |
Filed Date | 2009-04-30 |
United States Patent
Application |
20090107737 |
Kind Code |
A1 |
Reynolds; Joesph K ; et
al. |
April 30, 2009 |
MULTIPLE-SENSOR-ELECTRODE CAPACITIVE BUTTON
Abstract
Methods for determining actuation of a capacitive button having
at least three sensor electrode elements associated with at least
three distinct sensor electrodes are described. In one embodiment,
indicia from the at least three distinct sensor electrodes
associated with the at least three sensor electrode elements
comprising the capacitive button are received. At least three
electrode values are generated from the indicia. The at least three
electrode values are then utilized to determine actuation of the
capacitive button.
Inventors: |
Reynolds; Joesph K;
(Mountain View, CA) ; Dattalo; Tracy Scott; (Santa
Clara, CA) ; Fravel; John C; (San Jose, CA) ;
Baharav; Izhak; (Palo Alto, CA) ; Feland, III; John
M; (Sa Jose, CA) |
Correspondence
Address: |
SYNAPTICS C/O WAGNER BLECHER LLP
123 WESTRIDGE DRIVE
WATSONVILLE
CA
95076
US
|
Family ID: |
40581369 |
Appl. No.: |
12/259182 |
Filed: |
October 27, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61000784 |
Oct 28, 2007 |
|
|
|
Current U.S.
Class: |
178/18.06 |
Current CPC
Class: |
G01R 27/2605 20130101;
G06F 3/0448 20190501; G06F 3/044 20130101; G06F 3/0202
20130101 |
Class at
Publication: |
178/18.06 |
International
Class: |
G08C 21/00 20060101
G08C021/00 |
Claims
1. A capacitive button arrangement comprising: a first capacitive
button comprising: a first set of sensor electrode elements, said
first set of sensor electrode elements having at least three sensor
electrode elements associated with distinct sensor electrodes,
wherein said first set of sensor electrode elements is configured
to enable the generation of at least three electrode values for
determining actuation of said first capacitive button; and a second
capacitive button disposed noncontiguously with respect to said
first capacitive button, said second capacitive button comprising:
a second set of sensor electrode elements, said second set of
sensor electrode elements having at least three sensor electrode
elements associated with distinct sensor electrodes, wherein said
second set of sensor electrode elements is configured to enable the
generation of at least three electrode values for determining
actuation of said second capacitive button.
2. The capacitive button arrangement of claim 1 further comprising:
a tactile feature disposed proximate said first capacitive button,
said tactile feature for providing tactile feedback for said first
capacitive button.
3. The capacitive button arrangement of claim 1 wherein at least
one of said distinct sensor electrodes associated with said at
least three sensor electrode elements of said first set of sensor
electrode elements is capable of emitting electrical signals.
4. The capacitive button arrangement of claim 1 wherein at least
one of said distinct sensor electrodes associated with said at
least three sensor electrode elements of said first set is capable
of both emitting and receiving electrical signals.
5. The capacitive button arrangement of claim 1 wherein said second
capacitive button is disposed noncontiguously with respect to said
first capacitive button by spacing said first set of sensor
electrode elements from said second set of sensor electrode
elements by no less than one-half of a finger width.
6. The capacitive button arrangement of claim 1 further comprising:
a disambiguating electrode disposed proximate said first set of
sensor electrode elements, said disambiguating electrode configured
to enable distinguishing of user input intended to actuate said
first capacitive button from user input not intended to actuate
said first capacitive button.
7. The capacitive button arrangement of claim 1, wherein said first
set of sensor electrode elements has no more than four sensor
electrode elements.
8. The capacitive button arrangement of claim 1 wherein at least
two sensor electrode elements of said first set of sensor electrode
elements are physically interdigitated with each other.
9. The capacitive button arrangement of claim 1 wherein a sensor
electrode element of said first set of sensor electrode elements
and a sensor electrode element of said second set of sensor
electrode elements are associated with a same sensor electrode.
10. The capacitive button arrangement of claim 9 wherein said
sensor electrode element of said first set of sensor electrode
elements is physically closer to said sensor electrode element of
said second set of sensor electrode elements than to any other
sensor electrode element of said second set of sensor electrode
elements.
11. The capacitive button arrangement of claim 9 wherein said
sensor electrode element of said first set of sensor electrode
elements is physically farther away from said sensor electrode
element of said second set of sensor electrode elements than to any
other sensor electrode element of said second set of sensor
electrode elements.
12. The capacitive button arrangement of claim 9 wherein said
sensor electrode element of said first set of sensor electrode
elements and said sensor electrode element of said second set of
sensor electrode elements are disposed on a same side of said
capacitive button arrangement.
13. The capacitive button arrangement of claim 1 wherein said first
capacitive button has a size that enables actuation by a human
digit.
14. The capacitive button arrangement of claim 1 wherein said
sensor electrode elements of said first set of sensor electrode
elements are disposed symmetrically.
15. The capacitive button arrangement of claim 1, wherein at least
two sensor electrode elements of said first set of sensor electrode
elements have centers that are substantially equidistant from a
center of said first capacitive button.
16. The capacitive button arrangement of claim 1 wherein said first
capacitive button has a circular shape, and wherein said sensor
electrode elements of said first set of sensor electrode elements
occupy substantially equal sectors of said circular shape.
17. The capacitive button arrangement of claim 1 wherein said first
capacitive button has a central region, and wherein said sensor
electrode elements of said first set of sensor electrode elements
are disposed outside of said central region.
18. The capacitive button arrangement of claim 1 wherein said first
capacitive button has rectilinear portions, and wherein said sensor
electrode elements of said first set of sensor electrode elements
have angular sections.
19. The capacitive button arrangement of claim 1 wherein said
sensor electrode elements of said first set of sensor electrode
elements have substantially equal areas.
20. The capacitive button arrangement of claim 1 further
comprising: a third capacitive button comprising: a third set of
sensor electrode elements disposed between said first set of sensor
electrode elements and said second set of sensor electrode
elements, said third set of sensor electrode elements having at
least three sensor electrode elements associated with distinct
sensor electrodes, wherein no sensor electrode element of said
third set of sensor electrode elements is associated with any
sensor electrodes associated with any sensor electrode element of
said first set of sensor electrode elements, and wherein no sensor
electrode element of said third set of sensor electrode elements is
associated with any sensor electrodes associated with any sensor
electrode element of said second set of sensor electrode
elements.
21. A capacitive sensing device comprising: a substrate; a first
capacitive button coupled to said substrate, said first capacitive
button comprising: a first set of sensor electrode elements
disposed on said substrate, said first set of sensor electrode
elements having at least three sensor electrode elements associated
with distinct sensor electrodes of a plurality of sensor
electrodes; a second capacitive button coupled to said substrate,
said second capacitive button comprising: a second set of sensor
electrode elements disposed on said substrate, said second set of
sensor electrode elements having at least three sensor electrode
elements associated with distinct sensor electrodes of said
plurality of sensor electrodes; and a controller coupled to said
first capacitive button and said second capacitive button, said
controller configured to receive indicia from said plurality of
sensor electrodes, to generate at least three electrode values
using indicia received from sensor electrodes associated with said
first set of sensor electrode elements, and to utilize said at
least three electrode values to determine actuation of said first
capacitive button.
22. The capacitive sensing device of claim 21 wherein at least one
of said distinct sensor electrodes associated with said at least
three sensor electrode elements of said first set of sensor
electrode elements is capable of emitting electrical signals.
23. The capacitive sensing device of claim 21, wherein said first
capacitive button has no more than four sensor electrode
elements.
24. The capacitive sensing device of claim 21, wherein sensor
electrode elements of said first set of sensor electrode elements
have a symmetric layout.
25. The capacitive sensing device of claim 21, wherein sensor
electrode elements of said first set of sensor electrode elements
have substantially equal areas.
26. The capacitive sensing device of claim 21, wherein a sensor
electrode element of said first set of sensor electrode elements
and a sensor electrode element of said second set of sensor
electrode elements are associated with a same sensor electrode.
27. The capacitive sensing device of claim 21 wherein said first
capacitive button has a size configured to be actuated by a human
finger.
28. A method for determining actuation of a capacitive button
having at least three sensor electrode elements associated with at
least three distinct sensor electrodes, said method comprising:
receiving indicia from said at least three distinct sensor
electrodes comprising said capacitive button; generating at least
three electrode values from said indicia; and utilizing said at
least three electrode values to determine actuation of said
capacitive button.
29. The method for determining actuation of a capacitive button as
recited in claim 28, wherein said utilizing said at least three
electrode values to determine actuation of said capacitive button
comprises: comparing at least one of said at least three electrode
values to an activation threshold value.
30. The method for determining actuation of a capacitive button as
recited in claim 28, wherein said utilizing said at least three
electrode values to determine actuation of said capacitive button
comprises: determining a position of an input object with respect
to said capacitive button.
31. The method for determining actuation of a capacitive button as
recited in claim 28 further comprising: receiving indicia from a
disambiguating electrode disposed proximate to said capacitive
button; generating a disambiguating value from said indicia from
said disambiguating electrode; and utilizing said disambiguating
value to determine a false actuation of said capacitive button.
32. The method for determining actuation of a capacitive button as
recited in claim 28 further comprising: emitting electrical signals
using at least one of said at least three distinct sensor
electrodes, said electrical signals for effecting said indicia from
said at least three distinct sensor electrodes.
33. The method for determining actuation of a capacitive button as
recited in claim 28 further comprising: emitting electrical signals
using at least two of said at least three distinct sensor
electrodes, said electrical signals for effecting said indicia from
said at least three distinct sensor electrodes.
34. An electronic system comprising: an output device capable of
providing human-observable output; a plurality of capacitive
buttons comprising: a substrate; a first set of sensor electrode
elements disposed on said substrate, said first set of sensor
electrode elements having at least three sensor electrode elements
associated with distinct sensor electrodes of a plurality of sensor
electrodes; a second set of sensor electrode elements disposed on
said substrate, said second set of sensor electrode elements having
at least three sensor electrode elements associated with distinct
sensor electrodes of said plurality of sensor electrodes; and a
controller coupled to said plurality of capacitive buttons, said
controller configured to receive indicia from said plurality of
sensor electrodes, to generate at least three electrode values
using indicia received from sensor electrodes associated with said
first set of sensor electrode elements, to utilize said at least
three electrode values to determine actuation of said first
capacitive button, and to effect human-observable output using said
output device in response to actuation of said first capacitive
button.
35. The electronic system of claim 34, wherein said output device
capable of providing human-observable output is a sound device, and
wherein said controller is configured to effect human-observable
output using said output device in response to actuation of said
first capacitive button by producing a sound using said sound
device in response to actuation of said first capacitive
button.
36. The electronic system of claim 34, wherein said output device
capable of providing human-observable output is a force feedback
device, and wherein said controller is configured to effect
human-observable output using said output device in response to
actuation of said first capacitive button by providing haptic
feedback using said force feedback device in response to actuation
of said first capacitive button.
Description
RELATED U.S. APPLICATION
Provisional
[0001] This non-provisional application claims priority to the
co-pending provisional patent application Ser. No. 61/000,784,
Attorney Docket Number SYNA-20070619-A1.PRO, entitled "Capacitive
Buttons," with filing date Oct. 28, 2007, and assigned to the
assignee of the present invention, which is herein incorporated by
reference in its entirety.
BACKGROUND
[0002] Capacitive sensing devices are widely used in modern
electronic devices. For example, capacitive sensing devices have
been employed in music and other media players, cell phones and
other communications devices, remote controls, personal digital
assistants (PDAs), and the like. These capacitive sensing devices
are often used for touch based navigation, selection, or other
functions. These functions can be in response to one or more
fingers, styli, other objects, or combination thereof providing
input in the sensing regions of respective capacitive sensing
devices.
[0003] However, there exist many limitations to the current state
of technology with respect to capacitive sensing devices. As one
example, limitations are known to be associated with capacitive
button sensing systems.
SUMMARY
[0004] In various embodiments, methods for determining actuation of
a capacitive button having at least three sensor electrode elements
associated with at least three distinct sensor electrodes are
described. In one such embodiment, indicia from the at least three
distinct sensor electrodes are received. At least three electrode
values are generated from the indicia. The at least three electrode
values are utilized to determine actuation of the capacitive
button.
[0005] In various other embodiments, capacitive button apparatuses
are described. One such apparatus includes a first capacitive
button and a second capacitive button. The first capacitive button
has a first set of sensor electrode elements configured to enable
the generation of at least three electrode values for determining
actuation of the first capacitive button. This first set of sensor
electrode elements has at least three sensor electrode elements
associated with distinct sensor electrodes. The second capacitive
button has a second set of sensor electrode elements configured to
enable the generation of at least three electrode values for
determining actuation of the second capacitive button. This second
set of sensor electrode elements has at least three sensor
electrode elements associated with distinct sensor electrodes.
[0006] In order to improve capacitive button performance, such as
by reducing false actuations, supporting non-button actuation
input, and the like, capacitive buttons described herein uses
multiple sensor electrodes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The accompanying drawings, which are incorporated in and
form a part of this specification, illustrate embodiments of the
technology for multiple-sensor-electrode capacitive buttons and,
together with the description, serve to explain principles
discussed below:
[0008] FIG. 1 is a block diagram of an example capacitive button
arrangement in accordance with embodiments of the present
technology.
[0009] FIG. 2A is a block diagram of an example capacitive sensing
device and an enlarged view of example components within the
capacitive sensing device in accordance with embodiments of the
present technology.
[0010] FIG. 2B is a block diagram of an enlarged view of example
first and second capacitive buttons with interdigitated sensor
electrode elements in accordance with embodiments of the present
technology.
[0011] FIG. 3A is a block diagram of first and second capacitive
buttons with an input object at a first position with respect to
the capacitive buttons in accordance with embodiments of the
present technology.
[0012] FIG. 3B is a block diagram of first and second capacitive
buttons with an input object at a second position with respect to
the capacitive buttons in accordance with embodiments of the
present technology.
[0013] FIG. 3C is a block diagram of first and second capacitive
buttons with an input object at a third position with respect to
the capacitive buttons in accordance with embodiments of the
present technology.
[0014] FIG. 3D is a block diagram of first and second capacitive
buttons with an input object at a fourth position with respect to
the capacitive buttons in accordance with embodiments of the
present technology.
[0015] FIG. 3E is a block diagram of first and second capacitive
buttons with an input object at a fifth position with respect to
the capacitive buttons in accordance with embodiments of the
present technology.
[0016] FIG. 3F is a block diagram of first and second capacitive
buttons with two input objects concurrently in the sensing region
of the capacitive buttons in accordance with embodiments of the
present technology.
[0017] FIG. 4A is a diagram of a circular capacitive button with
three sensor electrode elements in accordance with embodiments of
the present technology.
[0018] FIG. 4B is a diagram of an annular capacitive button with
three sensor electrode elements surrounding an aperture in
accordance with embodiments of the present technology.
[0019] FIG. 4C is a diagram of a square-shaped capacitive button
with four sensor electrode elements in accordance with embodiments
of the present technology.
[0020] FIG. 4D is a diagram of a rectangular capacitive button with
three sensor electrode elements in accordance with embodiments of
the present technology.
[0021] FIG. 4E is a diagram of a circular capacitive button with
four sensor electrode elements in accordance with embodiments of
the present technology.
[0022] FIG. 5A is a diagram of a capacitive button with an emitter
sensor electrode element surrounding sensor electrode elements in
accordance with embodiments of the present technology.
[0023] FIG. 5B is a diagram of a capacitive button with a separate
emitter sensor electrode element surrounded by sensor electrode
elements in accordance with embodiments of the present
technology.
[0024] FIG. 5C is a diagram of a capacitive button with sensor
electrode elements capable of emitting as well as sensing signals
in accordance with embodiments of the present technology.
[0025] FIG. 6A is a diagram of four circular capacitive buttons
sharing four sensor electrodes in accordance with embodiments of
the present technology.
[0026] FIG. 6B is a diagram of four circular capacitive buttons
sharing four sensor electrodes in accordance with embodiments of
the present technology.
[0027] FIG. 7 is a block diagram of an example arrangement of
capacitive buttons in accordance with embodiments of the present
technology.
[0028] FIG. 8 is a cross-sectional view of a tactile feature in
accordance with embodiments of the present technology.
[0029] FIG. 9 is a flowchart of an example method for determining
actuation of a capacitive button in accordance with embodiments of
the present technology.
[0030] The drawings referred to in this description should not be
understood as being drawn to scale unless specifically noted.
DESCRIPTION OF EMBODIMENTS
[0031] Reference will now be made in detail to embodiments of the
present technology, examples of which are illustrated in the
accompanying drawings. While the present technology will be
described in conjunction with embodiments, it will be understood
that the descriptions are not intended to limit the present
technology to these embodiments. On the contrary, the descriptions
are intended to cover alternatives, modifications and equivalents,
which may be included within the spirit and scope as defined by the
appended claims. Furthermore, in the following detailed
description, numerous specific details are set forth in order to
provide a thorough understanding of embodiments of the present
technology. However, one of ordinary skill in the art will
understand that embodiments of the present technology 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 technology.
Overview of Discussion
[0032] Embodiments in accordance with the present technology
pertain to capacitive buttons and their usage. In one embodiment in
accordance with the present technology, the capacitive sensing
devices described herein improve distinguishing between input
intended to actuate a capacitive button and input not intended to
actuate a capacitive button. Indicia received from sensor
electrodes associated with a capacitive button are used to
determine electrode values. These electrode values are utilized to
determine the actuation status of the capacitive button. Positional
characteristics about one or more input objects may or may not be
determined in support of gauging the actuation status of a
capacitive button. The positional characteristics determined can
include a myriad of diverse measurements related to the object(s)
in a capacitive sensing region of the capacitive button, as
discussed further below. Possible input objects include fingers,
styli, and other input objects capable of conveying user input. The
term "finger" is used herein to refer to any digit on a hand,
including a thumb. The term "actuation" is used herein to refer to
turning a capacitive button ON. Conversely, the term "activation"
is used herein to refer to a sufficient user interaction that has
occurred with respect to a sensor electrode.
[0033] In various embodiments, a capacitive button arrangement
includes a plurality of multiple-sensor-electrode capacitive
buttons ("MSE capacitive buttons"). Each MSE capacitive button is
comprised of multiple sensor electrode elements belonging to
distinct sensor electrodes. Where it may otherwise be unclear, "MSE
capacitive button" is used in this document to distinguish from
capacitive buttons that do not use a multiple-sensor-electrode
approach. For example, a single capacitive button arrangement may
include capacitive buttons of different types, including any
combination of capacitive buttons having only a single sensor
electrode element, exactly two sensor electrode elements, three
sensor electrode elements, or any number of sensor electrode
elements.
[0034] A sensor electrode in a capacitive button arrangement may
have one or more sensor electrode elements. Thus, a single sensor
electrode may include sensor electrode elements in multiple
capacitive buttons, and thus be shared among those multiple
capacitive buttons. A sensor electrode element that forms a portion
of a sensor electrode is considered to belong to that sensor
electrode, and is also considered to be associated with that sensor
electrode. A set of sensor electrode elements including an element
forming a portion of a sensor electrode is considered to be
associated with that sensor electrode. Since the sensor electrode
elements and sensor electrodes are used for capacitance sensing,
they can also be termed "sensor electrode elements" and "sensor
electrodes," respectively.
[0035] In various embodiments, each MSE capacitive button of a
capacitive button arrangement is comprised of a set of sensor
electrode elements associated with a plurality of sensor
electrodes. Each of the sets of sensor electrode elements has at
least three elements associated with distinct ones of the plurality
of sensor electrodes. That is, each set of sensor electrode
elements includes separate elements that form portions of at least
three different sensor electrodes.
[0036] During operation, the plurality of sensor electrodes
provides indicia that are received by a controller. The indicia
reflect user input in the sensing region. Since user input in the
sensing region affects the electric field surrounding the sensor
electrodes, the indicia can be electric signals that change with
the electric field surrounding the sensor electrodes. For example,
the indicia may include voltages, currents, charges, frequencies,
time constants, or any other items that varies with changes in the
capacitive coupling to the sensor electrodes.
[0037] The controller utilizes the received indicia to generate at
least three electrode values for each MSE capacitive button. Since
one sensor electrode may have sensor electrode elements in multiple
capacitive buttons, one electrode value may be associated with
multiple capacitive buttons. Thus, the total number of electrode
values generated by the controller may be less than three times the
number of capacitive buttons, although that is not required. The
electrode values generated by the controller may be linearly or
non-linearly related to the capacitive coupling of the sensor
electrodes (e.g. some representation of the capacitive coupling
that is proportional to the change in capacitance, or that is
proportional to a reciprocal of the change in capacitance). Since
these electrode values are derived from indicia received from
sensor electrodes, they can also be termed "sensor electrode
values."
[0038] Oftentimes, the indicia and/or the electrode values is/are
conditioned or filtered by the controller. The controller may do
this by averaging, by subtracting baselines, by particular
weighting functions determined by the capacitive button design, and
the like.
[0039] The controller utilizes the electrode values to recognize
user input, such as to determine whether or not a capacitive button
is actuated. As discussed above, some embodiments determine
positional characteristics about the input objects as part of the
process for gauging the actuation status of a capacitive button
while other embodiments do not. That is, embodiments of the present
technology may calculate none, some, or all of the derivable
positional characteristics.
[0040] Positional characteristics encompass a myriad of different
information that may be derived about the interaction of input
devices with MSE capacitive buttons. Many of the positional
characteristics represent substantially independent spatial
measurements of the user input within the sensing region. Some
example positional characteristics represent estimates of the
locations of inputs along one or more dimensions, at an instance in
time or over a span of time. For example, the position of an input
may be determined with respect to a 2D plane defined by the touch
pad (e.g. as X and Y, as r and .theta., or as any other appropriate
set of coordinates).
[0041] Other examples of positional characteristics represent
estimates of the amount of capacitive coupling to an input (e.g.,
as Z); the amount of capacitive coupling changes with the distance
and size of the input, signals coupled into an input object, and
the like. Additional examples of positional characteristics may
include various time derivatives and integrals of other positional
characteristics (e.g. of X, Y, or Z). Further examples of
positional characteristics include averages, ratios, magnitudes,
and combinations of any of the foregoing.
[0042] An MSE capacitive button may support any type of user
interface. For example, they may be used with any of the devices
which can be supported by non-MSE capacitive buttons. Examples
include, and are not limited to: input devices such as keypads,
keyboards, and remote controls; media devices such as cameras,
video recorders or players, music recorders or players;
communications or organizational devices such as personal digital
assistants (PDAs), cell phones, GPS systems; and the like.
[0043] MSE capacitive buttons may also be indicated to the user in
various ways. For example, any number of shapes and sizes of
indicators may be placed between the sensor electrode elements and
the user. This may include primarily visual indicators such as
painted lines or lighted cutouts. This may also include primarily
tactile indicators such as bumps, ridges, depressions, and the
like. Additionally, according to some embodiments of the present
technology, capacitive buttons are well suited to effecting a
haptic response by providing information about anticipated or
current button actuation directly or indirectly to a controller of
a haptic feedback system.
[0044] The following discussion will begin with a detailed
description focused on aspects of the structure in accordance with
the present technology. This discussion will then be followed by a
detailed description focused on aspects of the operation in
accordance with the present technology.
Example Capacitive Button Arrangement
[0045] FIG. 1 is a block diagram of an example capacitive sensing
device 100 in accordance with embodiments of the present
technology. Capacitive sensing device 100 comprises a plurality of
noncontiguous MSE capacitive buttons (two are shown, as first
capacitive button 110 and second capacitive button 120) disposed on
substrate 107 and capable of sensing objects within capacitive
sensing region 135. First capacitive button 110, second capacitive
button 120, and controller 105 are all shown disposed on the same
substrate 107 in FIG. 1; disposing them on any number of separate
substrates in other embodiments is possible and contemplated. The
substrates can be rigid or flexible.
[0046] Capacitive sensing region 135 is a three-dimensional region
extending from the capacitive buttons. Input objects in sensing
region 135 may interact with the capacitive sensing device 100. The
size and shape of capacitive sensing region 135 is defined by the
mechanical and electrical characteristics of the capacitive sensing
device 100 (e.g. shapes and sizes of surrounding materials, layout
of electrodes and routing lines), the circuitry and algorithms of
controller 105, the performance desired, and the like.
[0047] The MSE capacitive buttons of capacitive sensing device 100
are comprised of different sets of sensor electrode elements, where
each set of sensor electrode elements have at least three members
that are associated with different sensor electrodes. In FIG. 1,
capacitive buttons 110 and 120 are each comprised of a set of three
sensor electrode elements exactly: first capacitive button 110 has
a first set including sensor electrode elements 117A-117C, and a
second capacitive button 120 has a set including sensor electrode
elements 127A-127C.
[0048] FIG. 1 shows a capacitive button arrangement in which sensor
electrodes are not shared between MSE capacitive buttons.
Specifically, the embodiment shown in FIG. 1 imposes a one-to-one
relationship between sensor electrode elements of the two MSE
capacitive buttons and a plurality of distinct sensor electrodes.
This means that the two MSE capacitive buttons 110 and 120 do not
have any sensor electrode elements associated with the same sensor
electrode. (e.g. sensor electrode elements 117A-117C and 127A-127C
all form portions of different sensor electrodes, and capacitive
button 110 and 120 have no sensor electrodes in common.)
[0049] Although not shown in FIG. 1, one or more sensor electrodes
in the capacitive sensing device 100 may be shared. The sharing may
occur between any combination of MSE capacitive buttons, non-MSE
capacitive buttons, other input devices, and the like. In the case
where a sensor electrode is shared between MSE capacitive buttons,
a many-to-one relationship exists between sensor electrode elements
associated with that shared sensor electrode itself. In such a
configuration, multiple sensor electrode elements, each forming a
part of a different MSE capacitive button, would belong to the same
sensor electrode. This many-to-one relationship allows a set of
sensor channels to support more capacitive buttons than possible if
a one-to-one relationship is imposed. This is discussed further
below.
[0050] Regardless of whether or not the sensor electrodes are
shared, each MSE capacitive button has at least three sensor
electrode elements that are associated with different sensor
electrodes. Thus, interaction with a capacitive button would cause
changes in at least three sensor electrodes.
[0051] In some embodiment, some or all of the sensor electrode
elements of an MSE capacitive button have a symmetric layout, and
are thus disposed symmetrically. The symmetry may include
rotational symmetry, mirror symmetry along one or more axes, or any
other applicable form of symmetry. In some other embodiments, some
or all of the sensor electrode elements of an MSE capacitive button
have substantially equal areas. In some further embodiments, the
sensor electrode elements of an MSE capacitive buttons all meet at
a central area of their respective MSE capacitive buttons.
[0052] In yet other embodiments of the present technology, the
sensor electrode elements of a capacitive button are disposed in
such a way that the centers of different sensor electrode elements
are substantially the same distance from a center of the capacitive
button. Thus, at least two sensor electrode elements of the MSE
capacitive button have centers that are substantially equidistant
from a center of the MSE capacitive button. One way to gauge
distances from the center is to examine estimated centroid
locations of the sensor electrode elements and their capacitive
button. The estimated centroid locations can be based on the area
of each sensor electrode element. For example, in many embodiments
where the capacitive button has approximately the shape traced out
by its sensor electrode elements, and where the sensor electrode
elements of the capacitive button are disposed about the center of
the capacitive button symmetrically, a centroid of a first sensor
electrode element of the capacitive button and a centroid of a
second sensor electrode element of the capacitive button is
substantially the same distance from the centroid of the capacitive
button. The estimated centroid location can also be based on a
weighted area of each sensor electrode element. For example, the
areas of sensor electrode elements of an MSE capacitive button may
be weighted by the amount of capacitive coupling that the sensor
electrode elements are anticipated to have with input objects on a
surface above the MSE capacitive button. In some embodiments, the
centroid calculation ignores areas of the sensor electrode elements
that are expected to experience little or no capacitive coupling
changes from users during operation (e.g. areas having far away
locations where significant capacitive coupling changes due to user
input are expected to occur, areas shielded from effects of user
input, and areas having dimensions or shapes that are expected to
experience little or no capacitive coupling changes--such as narrow
lines).
[0053] In further other embodiments, a combination of the above is
implemented. For example, the sensor electrode elements of an MSE
capacitive button may have both substantially equal areas and a
symmetric layout. Examples of this are shown in FIG. 1, where all
of the sensor electrode elements of capacitive button 110 (sensor
electrode elements 117A-117C) are substantially equal in area and
symmetrically disposed about a center of capacitive button 110.
Similarly, sensor electrode elements 127A-127C of capacitive button
120 are also substantially equal in area and symmetrically disposed
about a center of capacitive button 120.
[0054] Referring still to FIG. 1, sensor electrode elements
117A-117C and 127A-127C are ohmically coupled to controller 105 via
routing traces 130. Furthermore, as noted in FIG. 1, first
capacitive button 110 is noncontiguous with second capacitive
button 120. This noncontiguity may be achieved by spacing the sets
of sensor electrode elements apart. In some embodiments, first
capacitive button 110 and second capacitive button 120 are disposed
noncontiguously with respect to each other by spacing the first set
of sensor electrode elements from the second set of sensor
electrode elements (e.g. 117A-117C from the set of sensor electrode
elements 127A-127C) by no less than one-half a finger width. In
other embodiments, sensor electrode elements of noncontiguous
capacitive buttons may be disposed closer to each other than
one-half a finger width. The exact measure of one-half finger width
would depend largely on the size of expected users. For many adult
humans, one-half a finger width is about 3-8 (or even up to 10) mm
for the pointer, middle, ring, or little fingers, while one-half a
finger width would be about 6-12 (or even up to 15) mm for thumbs.
The applicable finger width may vary depending on the orientation
of the finger relative to the capacitive buttons (e.g. a 2-D
projection of the input object presented to the capacitive button
may be oval). The button spacing may vary as well with these
considerations.
[0055] Thus, although FIG. 1 shows first capacitive button 110 in
relatively close proximity to second capacitive button 120, FIG. 1
is meant to be a block diagram that is not strictly drawn to scale.
Thus, first capacitive button 110 may not be in relatively close
proximity to second capacitive button 120 in various physical
implementations. For example, capacitive buttons 110 and 120 may be
physically far apart, such as on different sides of an electronic
display. As other examples, capacitive buttons 110 and 120 may also
be spaced to make room for other user input devices such as
mechanical switches or pointing sticks, to improve usability, to
accommodate industrial design preferences, and the like.
[0056] Embodiments in accordance with the present technology are
well suited to capacitive buttons having three or more sensor
electrode elements each. In many embodiments, the capacitive
buttons will have no more than four sensor electrode elements.
Where a capacitive button has more than three sensor electrode
elements, and especially if the capacitive button has more than
four sensor electrode elements, it may be advantageous to ohmically
couple some of the sensor electrode elements within the same
capacitive button together. For example, for a capacitive button
having six sensor electrode elements, it may be advantageous to
short every three sensor electrode elements together and use them
to form portions of the same sensor electrode. Other embodiments
may prefer associating the six sensor electrode elements with 3, 4,
5, or 6 sensor electrodes.
[0057] Similarly, embodiments in accordance with the present
technology are well suited to use with sensor electrodes that are
shared or not shared between capacitive buttons. It should further
be noted that embodiments in accordance with the present technology
are well suited to any of various sizes, shapes, layouts,
configurations, or orientations of sensor electrodes, sensor
electrode elements, routing times, and the like. In many
embodiments, the sensor electrode elements of the capacitive button
are configured such that the capacitive button has a size that
enables actuation by a human digit, such as a finger or a toe.
[0058] Referring to FIG. 2A, first capacitive button 110 includes
sensor electrode elements A.sub.1, B.sub.1 and C.sub.1 and second
capacitive button 120 includes sensor electrode elements A.sub.2,
B.sub.2 and D.sub.2. Sensor electrode A comprises electrode
elements A.sub.1 and A.sub.2, which are electrically coupled with
each other. Sensor electrode B comprises sensor electrode elements
B.sub.1 and B.sub.2, which are electrically coupled with each
other. Sensor electrode C comprises electrode element C.sub.1, and
sensor electrode D comprises electrode element D.sub.2. Thus, these
six sensor electrode elements are associated with the four sensor
electrodes A, B, C, and D, all of which are electrically coupled to
controller 105.
[0059] As is discussed, the present technology is well suited to
MSE capacitive buttons having sensor electrode elements of varying
arrangements, shapes, and sizes. For example, FIG. 4A shows a
circular MSE capacitive button comprising three sensor electrode
elements in accordance with embodiments of the present technology.
Each of the sensor electrode elements occupies a substantially
equal sector of the circular capacitive buttons shape. This set of
sensor electrode elements also has both rotational and mirror
symmetries. Further, the sensor electrode elements meet at a center
of the capacitive button.
[0060] FIG. 4B shows a MSE capacitive button having an "aperture"
400 in the pattern of sensor electrode elements, in accordance with
embodiments of the present technology. Although a circular
capacitive button having three sensor electrode elements is shown
in FIG. 4B, it is understood that apertures can be introduced in
sensor patterns of a variety of different MSE capacitive button
designs. The aperture 400 may be a true hole that extends through
the sensor electrode pattern and any substrates. Or, the aperture
400 may be simply an area where no sensor electrode element
material is placed--the substrate may be solid or something else
may be placed in aperture 400.
[0061] In FIG. 4B, a single aperture 400 is shown, positioned in a
central region of the capacitive button, and the sensor electrode
elements are placed outside and about the aperture. However, other
numbers of apertures may be included in a capacitive button, and
they may be located in other places other than a central region of
the capacitive button. Similar to the example of FIG. 4A, the
sensor electrode elements shown in FIG. 4B are about equal in area.
The set of sensor electrode elements has both rotational and mirror
symmetries, and the sensor electrode elements meet at a center of
the capacitive button.
[0062] FIG. 4C shows a square-shaped MSE capacitive button
comprising four square-shaped sensor electrode elements in
accordance with embodiments of the present technology. Similar to
the example of FIG. 4A, each of the sensor electrode elements are
about equal in area, the set of sensor electrode elements has both
rotational and mirror symmetries, and the sensor electrode elements
meet at a center of the capacitive button. While square-shaped
sensor electrode elements are shown in FIG. 4C, rectangles of other
aspect ratios are possible. For example, other aspect ratios may be
more useful depending on the input object size and orientation, on
spacing between any capacitive buttons, and the like.
[0063] FIG. 4D shows another rectangular MSE capacitive button.
However, this one has three sensor electrode elements in accordance
with embodiments of the present technology. These three sensor
electrode elements are of unequal shapes, but still have
substantially equal areas. The set of sensor electrode elements
also has mirror symmetry, and the sensor electrode elements meet at
a center of the capacitive button.
[0064] The embodiments shown in FIGS. 4C and 4D are examples of
capacitive buttons with rectilinear portions, where each button has
sensor electrode elements with angular sections. In addition to
rectangles, other such capacitive buttons with rectilinear portions
and angular sensor electrode elements are possible. For example,
the capacitive button may have a "T" or "+" shape.
[0065] FIG. 4E shows a circular MSE capacitive button comprising
four sensor electrode elements in accordance with embodiments of
the present technology. Like the example shown in FIG. 4A, each of
the sensor electrode elements occupies an approximately
equally-sized sector of a circle. The set of sensor electrode
elements also has both rotational and mirror symmetries, and the
sensor electrode elements meet at a center of the capacitive
button.
[0066] FIG. 4A-4E all show sets of sensor electrode elements where
all sensor electrode elements in a set have substantially equal
areas. However, some embodiments may have sets where only some or
none of the sensor electrode elements are similar in area.
Similarly, FIG. 4A-4E all show sets of sensor electrode elements
that have some type of symmetry and all meet at a center of the
capacitive button and other common characteristics. However, other
embodiments may not have such characteristics.
[0067] Continuing with FIG. 2A, a block diagram is shown of an
example capacitive sensing device 100 with a controller coupled
with noncontiguous capacitive buttons in accordance with
embodiments of the present technology. The first capacitive button,
typically shown as 205, is disposed on substrate 107. First
capacitive button 205 is coupled with controller 105 via routing
traces typically shown as 130. First capacitive button 205 is
comprised of three sensor electrode elements A.sub.1, B.sub.1, and
C.sub.1. Dielectric material such as plastic (not shown) usually
covers any conductive material (e.g. material comprising the sensor
electrode elements and routing traces) that would otherwise be
exposed to an assembler or user. In various embodiments, this
protects the sensor electrode elements from the environment,
prevents electrical shorts between an input object and the
conductive material, and/or controls the capacitive coupling
experienced by the sensor electrodes.
[0068] Similarly, a second capacitive button, typically shown as
210, is also disposed on substrate 107 and coupled with controller
105 via routing traces typically shown as 130. Second capacitive
button 210 is comprised of three sensor electrode elements A.sub.2,
B.sub.2, and D.sub.2. Of note and as described herein, sensor
electrode elements A.sub.1 and A.sub.2 are ohmically coupled with
each other by both being routed to one sensing channel of
controller 105 (a first sensing channel). Thus, sensor electrode
elements A.sub.1 and A.sub.2 are sensor electrode elements of the
first and second capacitive buttons 205 and 210, respectively, and
are associated with a same sensor electrode A. Specifically, each
of the sensor electrode elements A.sub.1 and A.sub.2 forms a
portion of sensor electrode A, and sensor electrode A is shared by
the first and second capacitive buttons 205 and 210. Similarly,
sensor electrode elements B.sub.1 and B.sub.2 form one sensor
electrode B and are routed to one sensing channel of controller 105
(a second sensing channel). Thus, electrode elements B.sub.1 and
B.sub.2 are sensor electrode elements of the first and second
capacitive buttons, 205 and 210, respectively, and are associated
with the same sensor electrode B, and sensor electrode B is shared
by the first and second capacitive buttons 205 and 210. Also of
note is that sensor electrode elements C1 and D2 are not routed to
any other sensor electrode elements. Thus, sensor electrode C is
part of the first capacitive button 205 only, and sensor electrode
D is part of the second capacitive button 210 only. Embodiments in
accordance with the present technology are well suited to use with
various numbers of shared sensor electrodes. In those embodiments
where capacitive buttons have shared electrodes, the capacitive
buttons are constructed to have at least one sensor electrode not
in common (i.e. the combinations of sensor electrodes associated
with the capacitive buttons differ).
[0069] In the upper portion of FIG. 2A, first capacitive button
205, second capacitive button 210, and portions of routing traces
130 are shown disposed within an upper dotted box T. As discussed
below in detail, for purposes of clarity, FIG. 2A also includes an
enlarged view of the features disposed within a lower dotted box
T.
[0070] Controller 105 includes or is coupled with activation
identification mechanism 220. Controller 105 may also include or be
coupled with positional characteristics analyzing unit 218, if
positional characteristics are determined as part of the button
actuation analysis process. The functional operation of positional
characteristics analyzing unit 218 and activation identification
mechanism 220 are discussed below in detail.
[0071] FIG. 2A also shows a disambiguating electrode 215 as a
dotted box. Disambiguating electrode 215 is disposed proximate to
the set of sensor electrode elements of the first capacitive button
205. Disambiguating electrode 215 is configured to help distinguish
user input intended to actuate the first capacitive button 205 from
user input not intended to actuate the first capacitive button
205.
[0072] In many embodiments, disambiguating electrode 215 generates
indicia reflecting changes in capacitive coupling experienced by
the disambiguating electrode 215. Controller 105 processes the
indicia from disambiguating electrode 215 to produce electrode
values correlated to the disambiguating electrode 215. Controller
105 examines these disambiguating electrode values to better
distinguish between input intended to cause button actuation and
input not intended to cause button actuation.
[0073] For example, the disambiguating electrode values may help
controller 105 differentiate between input provided by multiple
smaller objects in the sensing region and input provided by a
single, larger object in the sensing region. In many embodiments,
input provided by multiple, smaller objects may be more likely to
provide valid button input (e.g. it may be caused by finger
presses), and input provided by a single, large object may be less
likely to provide valid button input (e.g. it may be caused by
palms of hands or cheeks of faces). Thus, in some embodiments,
controller 105 is configured to suppress button actuations when a
large object is determined to be interacting with the capacitive
button arrangement. In some other embodiments, controller 105 is
configured to inhibit (e.g. reject, suppress, or ignore) user
inputs or indicia that would otherwise cause button actuations in
response to disambiguating electrode values that indicate high
enough probabilities that the user inputs are not meant to result
in button actuations.
[0074] Although FIG. 2A shows disambiguating electrode 215 as a
single, large electrode surrounding both first and second
capacitive buttons 205 and 210, it is understood that other
embodiments may not implement any disambiguating electrodes. In
addition, other embodiments may implement any number of
disambiguating electrodes with any shape, size, and configuration
applicable to the capacitive sensing device design. For example, a
disambiguating electrode may be implemented as a conductive trace
or pattern located between sets of sensor electrode elements of two
different capacitive buttons.
[0075] Referring now to FIG. 2B, a block diagram of example
noncontiguous first and second capacitive buttons with
interdigitated sensor electrode elements, in accordance with
embodiments of the present technology is shown. In various
embodiments, the first capacitive button 205 has a first set of
sensor electrode elements. The first set of sensor electrode
elements includes at least three sensor electrode elements
associated with distinct sensor electrodes, and at least two sensor
electrode elements of that first set are physically interdigitated
with each other. That is, portions of at least two sensor electrode
elements "poke into" each other. In the case shown in FIG. 2B,
first capacitive button 205 comprises a set of three sensor
electrode elements, A.sub.1, B.sub.1, and C.sub.1, all of which are
interdigitated with each other, Thorn-shaped features (feature 230
is labeled for sensor electrode element A.sub.1) of each sensor
electrode element, A.sub.1, B.sub.1, and C.sub.1, extend into a
thorn-shaped space in an adjacent electrode element, B.sub.1,
C.sub.1, and A.sub.1. Of note, embodiments of the present
technology are well suited for interdigitation in any number of
shapes and forms, and numbers and shapes other than single thorns
are contemplated.
[0076] FIGS. 5A, 5B, and 5C show arrangements useful in some
embodiments using "transcapacitive" sensing schemes. "Absolute"
capacitive sensing schemes focus on changes in the amount of
capacitive coupling between objects external to the sensing devices
and sensor electrodes of the sensing device. In contrast,
"transcapacitive" sensing schemes focus on changes in the amount of
capacitive coupling between electrodes of the sensing device. Some
transcapacitive embodiments of capacitive buttons, each having at
least three sensor electrode elements, utilize separate emitter and
receiver sensor electrode elements. The emitter sensor electrode
elements are parts of emitter sensor electrodes, which are sensor
electrodes capable of emitting electrical signals. The receiver
sensor electrode elements are part of receiver sensor electrodes,
which are sensor electrodes capable of receiving electrical signals
from emitter sensor electrodes. Some transcapacitive embodiments of
capacitive buttons, each having at least three sensor electrode
elements, utilize sensor electrode elements of sensor electrodes
capable of both emitting and receiving electrical signals. In many
embodiments using either absolute or transcapacitive sensing, the
objects external to the sensing devices are coupled to the chassis
grounds of the sensing devices.
[0077] Referring now to FIG. 5A, a diagram of a capacitive button
with a separate emitter sensor electrode element 500 surrounding
receiver sensor electrode elements 505, 510, and 515 is shown in
accordance with embodiments of the present technology. The emitter
sensor electrode element 500 is associated with an emitter sensor
electrode. In the embodiment shown in FIG. 5A, there is one emitter
sensor electrode element 500 per capacitive button, although
multiple emitter sensor electrode elements may be included per
capacitive button. Thus, in transcapacitive sensing schemes such as
those described in conjunction with FIG. 5A, the capacitive button
arrangement includes at least one emitter sensor electrode element
that is capacitively coupled with the set of receiver sensor
electrode elements of the capacitive button. The emitter sensor
electrode element is configured to emit electrical signals to be
received by the set of receiver sensor electrode elements.
[0078] Emitter sensor electrode element 500 may surround the
receiver sensor electrode elements 505, 510, and 515 that receive
signals emitted by the emitter sensor electrode element 500, as
shown in FIG. 5A. However, in other embodiments and as shown in
FIG. 5B, the emitter sensor electrode element may be in an internal
portion, such as a central portion, of the capacitive button. The
internally located emitter sensor electrode element is surrounded
by the receiver sensor electrode elements configured to receive
signals emitted by the emitter sensor electrode.
[0079] It is understood that if additional MSE capacitive buttons
are introduced to the arrangement shown in FIG. 5A, the emitter
sensor electrode including emitter sensor electrode element 500 may
or may not be shared between the capacitive buttons. That is, each
capacitive button may have its own emitter sensor electrode
element, or multiple capacitive buttons may share the same emitter
sensor electrode (or even the same emitter sensor electrode
element, if the element is properly shaped and placed). Similarly,
receiver sensor electrodes may be shared or not shared between any
MSE capacitive buttons added to the configuration shown in FIG.
5A.
[0080] It is also understood that the configuration shown in FIG.
5A can be driven in other ways. For example, in some embodiments,
the element 500 is a receiver sensor electrode element, while the
elements 505, 510, and 515 are independent emitter sensor electrode
elements.
[0081] Referring now to FIG. 5B, a diagram of a capacitive button
with a separate emitter sensor electrode element 520 surrounded by
receiver sensor electrode elements 525, 530, and 535 in accordance
with embodiments of the present technology is shown. In the
embodiment shown in FIG. 5B, emitter sensor electrode element 520
may be in a central portion of the capacitive button, surrounded by
the receiver sensor electrode elements 525, 530, and 535, and
configured to receive signals emitted by emitter sensor electrode
element 520.
[0082] Referring now to FIG. 5C, a diagram of a capacitive button
with three sensor electrode elements 540, 545, and 550, at least
one of which is capable of emitting as well as sensing signals in
accordance with embodiments of the present technology, is shown.
The sensor electrode elements 540, 545, and 550 are associated with
distinct sensor electrodes A, B, and C, respectively. At least one
of the distinct sensor electrodes (e.g. A, B, and/or C) associated
with the sensor electrode elements 540, 545, and 550 of the
capacitive button is capable of both emitting and receiving
electrical signals. In such a case, the sensor electrode elements
540, 545, and 550, may be interdigitated with each other as shown
in FIG. 5C, interdigitated in some other manner (e.g. 2B), or not
be interleaved at all (e.g. have shapes similar to what are shown
in the other figures).
[0083] In one embodiment of the example shown in FIG. 5C, the
following process occurs during operation. At a first time, sensor
electrode A emits signals while sensor electrodes B C receive.
Then, at a second time, sensor electrode B emits signals while at
least sensor electrode C receives. This approach provides
interaction information between sensor electrodes A-B, A-C, and
B-C, which provides three independent capacitive measurements based
on the three sensor electrodes A-C having sensor electrode elements
in the capacitive button.
[0084] It can be seen that multiple other ways of implementing
transcapacitive sensing using the configuration shown in FIG. 5C
are possible. For example, adding to the process described above,
sensor electrode A can also receive during the second time when
sensor electrode B emits. Alternatively, also adding to the process
described above, there can be a third time during which sensor
electrode C emits while sensor electrodes A and B receive. As a
separate example, sensor electrodes A and B can emit different
signals while sensor electrode C receives during a first time, then
sensor electrode A can emit while at least sensor electrode B
receives.
[0085] It is understood that if additional MSE capacitive buttons
are introduced to the arrangement shown in FIG. 5C, the sensor
electrodes may or may not be shared or not shared between
capacitive buttons. Emitter sensor electrodes are also termed
"drivers," "driver electrodes," "driver sensor electrodes,"
"emitters," "emitter electrodes," and the like. Receiver electrodes
are also termed "detectors," "detector electrodes," "detector
sensor electrodes," "receivers," "receiver electrodes," and the
like.
[0086] Accidental button actuation is often a bigger issue in
embodiments sharing sensor electrodes between capacitive buttons
than in embodiments not sharing sensor electrodes between
capacitive buttons. This is because, when sensor electrodes are
shared between capacitive buttons, inputs that interact with
different sensor electrode elements of different capacitive buttons
may produce results that mimic inputs that properly actuate another
capacitive button. As a more specific example, a capacitive button
arrangement with shared sensor electrodes may include a first
capacitive button having three sensor electrode elements belonging
to of sensor electrodes A-B-C, a second capacitive button having
three sensor electrode elements belonging to sensor electrodes
B-C-D, and a third capacitive button having three sensor electrode
elements belonging to sensor electrodes A-C-D. An input that
interacts with sensor electrode elements B and C of the second
capacitive button and sensor electrode element A of the third
capacitive button may mimic an input that properly interacts with
sensor electrode elements A, B, and C of the first capacitive
button. This may result in an unintended actuation of the first
capacitive button.
[0087] Referring to FIG. 6A, a diagram of four capacitive buttons,
600, 605, 610, and 615 sharing four sensor electrodes in accordance
with embodiments of the present technology is shown. The capacitive
button arrangement shown in FIG. 6A disposes buttons 600, 605, 610,
and 615 in a straight line. Other embodiments may involve layouts
with more or fewer capacitive buttons in linear or nonlinear
arrangements. For example, various embodiments may include
radically different numbers of capacitive buttons laid out in
substantially different patterns.
[0088] In the embodiment shown in FIG. 6A, each of the capacitive
buttons comprises a set of at least three sensor electrode
elements. The orientation of the different capacitive buttons and
the layout of the different sensor electrode elements associated
with the same sensor electrodes in those capacitive buttons are
selected such that the sensor electrode elements are positioned to
correspond with each other in a way that places them closer
together. This design can help reduce accidental button actuation,
especially when sensor electrodes are shared between capacitive
buttons. For example, an input that interacts with all of one
capacitive button and accidentally interacts with a small part of
an adjacent capacitive button may trigger fewer accidental
actuations. This may be especially helpful in cases where
capacitive buttons are placed less than half an input object width
apart (e.g. less than half a finger width apart).
[0089] In some embodiments, a first capacitive button has a first
set of sensor electrode elements and a second capacitive button has
a second set of sensor electrode elements. A sensor electrode
element of the first set is associated with the same sensor
electrode as a sensor electrode element of the second set. The
sensor electrode element of the first set is disposed to be
physically closer to the sensor electrode element of the second set
than any other sensor electrode element of the second set.
Depending on the embodiment, the distance used to compare closeness
can be the shortest distance from closest parts of sensor electrode
elements, from centers of the sensor electrode elements, or the
like. For some capacitive button designs, the resulting arrangement
can be termed to have sensor electrode elements of shared sensor
electrodes "face" each other in adjacent capacitive buttons.
[0090] In the embodiment shown in FIG. 6A, first capacitive button
600 and second capacitive button 605 each has three sensor
electrode elements, and first capacitive button 600 and second
capacitive button 605 have at least one shared sensor electrode in
common. Specifically, sensor electrode A has sensor electrode
elements in the first and second capacitive buttons 600 and 605
(sensor electrode elements A.sub.1 in the first capacitive button
600 and sensor electrode elements A.sub.2 in the second capacitive
button 605). The A.sub.1 sensor electrode element is arranged to be
physically closer to the A.sub.2 sensor electrode element than to
any of the other sensor electrode elements of the second capacitive
button 605. As further examples, similar placements can be seen for
the D.sub.3 and D.sub.4 sensor electrode elements of third
capacitive button 610 and fourth capacitive button 615. It is
understood that sensor electrode elements of shared sensor
electrodes need not be arranged in such a way between adjacent
capacitive buttons.
[0091] Also shown in FIG. 6A is how sensor electrode elements of a
shared sensor electrode may be disposed on a same side of the
capacitive button arrangement. In some embodiments, a first
capacitive button has a first set of sensor electrode elements and
a second capacitive button has a second set of sensor electrode
elements. A first sensor electrode element of the first set is
associated with the same sensor electrode as a second sensor
electrode element of the second set. The first sensor electrode
element and the second sensor electrode element are disposed on a
same side of the capacitive button arrangement. This design can
help reduce accidental button actuations, especially when sensor
electrodes are shared between capacitive buttons. For example, if
input is presented from that same side where the first and second
sensor electrode elements are disposed, and interacts with multiple
capacitive buttons, fewer accidental button actuations may
result.
[0092] In the embodiment shown in FIG. 6A, first capacitive button
600, second capacitive button 605, and third capacitive button 610
each has three sensor electrode elements, and all three capacitive
buttons 600, 605, and 610 share sensor electrode B (sensor
electrode element B.sub.1 in the first capacitive button 600,
sensor electrode element B.sub.2 in the second capacitive button
605, and sensor electrode element B.sub.3 in the third capacitive
button 610). The sensor electrode elements B.sub.1 and B.sub.2 are
arranged to both be on the same side of the arrangement (the "top"
side of FIG. 6A as shown). Similarly, sensor electrode elements
B.sub.2 and B.sub.3 are arranged to both be on the same side of the
arrangement, as are sensor electrode elements B.sub.1 and B.sub.3.
In fact, all three sensor electrode elements B.sub.1, B.sub.2, and
B.sub.3 are arranged to be on the same side. As a further example,
similar placements can be seen for the C.sub.2, C.sub.3 and C.sub.4
sensor electrode elements of second capacitive button 605, third
capacitive button 610, and fourth capacitive button 615 (on a
"bottom" side of FIG. 6A as shown). It is understood that sensor
electrode elements of shared sensor electrodes need not be arranged
in such a way.
[0093] Referring to FIG. 6B, a diagram of four other capacitive
buttons 650, 655, 660, and 665 sharing four sensor electrodes in
accordance with embodiments of the present technology is shown.
Each of the capacitive buttons 650, 655, 660, and 665 comprises a
set of at least three sensor electrode elements. Sensor electrode
elements associated with the same sensor electrode are positioned
to correspond with each other in a way that places them farther
apart. This design can help reduce accidental button actuation,
especially when sensor electrodes are shared between capacitive
buttons. For example, an input that simultaneously interacts with
large parts of multiple capacitive buttons may trigger fewer
accidental actuations. This may be especially helpful in cases
where capacitive buttons are placed more than half an input object
width apart (e.g. more than half a finger width apart).
[0094] In many such embodiments where multiple capacitive buttons
share multiple sensor electrodes, the minimum separation distance
between sensor electrode elements of shared sensor electrodes are
substantially maximized.
[0095] In some embodiments, a first capacitive button has a first
set of sensor electrode elements and a second capacitive button has
a second set of sensor electrode elements. A first sensor electrode
element of the first set is associated with the same sensor
electrode as a second sensor electrode element of the second set.
The first sensor electrode element is disposed to be physically
farther away from the second sensor electrode element than any
other sensor electrode element of the second set of sensor
electrode elements.
[0096] In the embodiment shown in FIG. 6B, the capacitive buttons
650, 655, 660, 665 each has three sensor electrode elements
associated with sensor electrodes chosen from a plurality of four
sensor electrodes A-D. As can be seen in FIG. 6B, the sensor
electrode elements of the same sensor electrode are placed as far
apart from each other as reasonable. For example, sensor electrode
element C.sub.1 of first capacitive button 650 is farther apart
from sensor electrode element C.sub.2 of second capacitive button
655 than the other sensor electrode elements A.sub.2 and B.sub.2 of
second capacitive button 655.
[0097] FIG. 7 is a block diagram of an example arrangement of
capacitive buttons in accordance with embodiments of the present
technology. FIG. 7 illustrates embodiments where neighboring
capacitive buttons are designed not to share any sensor electrodes
(have no sensor electrodes in common). This is accomplished by
arranging the capacitive buttons and their associated sets of
sensor electrode elements such that a first and second capacitive
button having shared sensor electrodes are separated by a third
capacitive button having no sensor electrodes in common with the
first and second capacitive buttons.
[0098] Said in another way, FIG. 7 illustrates embodiments where a
capacitive sensing device has a first capacitive button having a
first set of sensor electrode elements and a second capacitive
button having a second set of sensor electrode elements. The first
and second capacitive buttons share at least one sensor electrode,
such that a first sensor electrode element of the first set and a
second sensor element of the second set are associated with a same
sensor electrode. The capacitive sensing device further includes a
third capacitive button with a third set of sensor electrode
elements disposed between the first set of sensor electrode
elements and the second set of sensor electrode elements. The third
set of sensor electrode elements has at least three sensor
electrode elements associated with distinct sensor electrodes,
where no sensor electrode element of the third set of sensor
electrode elements belongs to the same sensor electrode as any
sensor electrode element of the first or second sets of sensor
electrode elements.
[0099] Rectangular capacitive buttons are shown in FIG. 7, with
each capacitive button having a set of sensor electrode elements.
Two groups of capacitive buttons (group m and group n) are shown in
FIG. 7, and include non-overlapping pluralities of sensor
electrodes (sensor electrodes A-D and sensor electrodes E-H). As
shown in FIG. 7, capacitive buttons in group m (capacitive buttons
700, 710, 725, and 735) share sensor electrodes A-D, and capacitive
buttons in group n (capacitive buttons 705, 715, 720, and 730)
share sensor electrodes E-H.
[0100] As shown in FIG. 7, the capacitive buttons are arranged such
that capacitive buttons in group m (capacitive buttons 700, 710,
725, and 735) are separated by capacitive buttons outside of group
m. Specifically, they are interspersed with capacitive buttons in
group n (capacitive buttons 705, 715, 720, and 730). Thus, in this
arrangement, neighboring capacitive buttons do not share any sensor
electrodes. This approach may be helpful in avoiding unintentional
button actuations. For example, a particular large input object
that simultaneously interacts with multiple neighboring capacitive
buttons would be less likely to trigger a valid combination of
sensor electrode responses. As a specific example, no capacitive
button shown in FIG. 7 uses the sensor electrode combination of
B-A-H. An input object located between capacitive buttons 700 and
705 may trigger such a response, but would not accidentally actuate
another button.
[0101] In many embodiments with where multiple capacitive buttons
share multiple sensor electrodes, some capacitive buttons are
placed close to each other while other capacitive buttons are
placed far apart. In such cases, the approaches illustrated in
FIGS. 6A, 6B, and 7 can be combined as appropriate. For example,
the orientation and/or positioning of the sensor electrode elements
of some capacitive button combinations (e.g. those close to each
other) can be selected to optimize for the approach shown in FIG.
6A, while the orientation and/or positioning of sensor electrode
elements of other capacitive button combinations (e.g. those far
apart from each other) can be selected to optimize the approach
shown in FIG. 6B. As another example, different groups of
capacitive buttons (the groups sharing non-overlapping pluralities
of sensor electrodes) can be placed to increase or decrease the
distance between sensor electrode elements of the same sensor
electrode, as appropriate. For example, the orientation and
positioning of the sensor electrode elements shown in FIG. 7 are
selected for a separation distance between the upper and lower rows
of capacitive buttons that is large compared to the typical width
of expected input objects, and for a separation distance between
same-group-buttons in the same row is greater than the typical
width of expected input objects.
[0102] FIG. 8 is a cross-sectional view of a tactile feature
configured to provide tactile feedback for a capacitive button in
accordance with embodiments of the present technology.
Specifically, FIG. 8 shows tactile feature 805 disposed proximate
to a capacitive button (not shown) located in structure 810.
Tactile feature 805 can be used to provide tactile feedback to
input object 800 (a finger is shown) to help a user in locating the
capacitive button in structure 810, or to help inform a user of
button actuation as the input object 800 interacts with the
capacitive button located in structure 810. In particular, the
tactile feedback may be used to help the user locate the input
object 800 laterally.
[0103] Although a single protrusion is shown in FIG. 8, it is
understood that any combination of protrusions, ridges,
depressions, textures, other elements, and the like can be used to
provide tactile feedback feature 805. Further, embodiments may
position tactile features around or about central regions of
capacitive buttons, or elsewhere in relation to the capacitive
buttons.
Operation
[0104] As discussed above, in embodiments in accordance with the
present technology, a capacitive button comprising a set of at
least three sensor electrode elements associated with distinct
sensor electrodes, offer improved button performance. Indicia
received from sensor electrodes associated with a capacitive button
are used to determine electrode values. These electrode values are
utilized to determine the actuation status of the capacitive
button. Positional characteristics about one or more input objects
may be determined while gauging the actuation status of a
capacitive button. Thus, determining the actuation status of the
capacitive button may involve determining one or more positional
characteristics of one or more input objects, and distinguishing
between input intended for button actuation from other input not
intended for button actuation (e.g. swiping gestures, input that
interacts with multiple capacitive buttons simultaneous, and the
like).
[0105] In some embodiments, a capacitive button may be tuned to
actuate if an input object makes physical contact with a surface
correlated with the capacitance button, and not if the input object
is not in contact with the surface. However, physical contact is
not inherently required for interaction with a capacitive button.
An input object in a sensing region of the capacitive button, and
hovering over a surface correlated to the capacitive button, may
interact with it. Enough changes in capacitive coupling may result
from such hovering input object for button actuation to occur.
Thus, in other embodiments of the present technology, a capacitive
button may be tuned to actuate in some cases when the input object
is not in contact with any surfaces correlated with the capacitive
button.
[0106] As will be described in detail below, FIGS. 3A-3E show
representations of an input object interacting with capacitive
buttons. Specifically, FIGS. 3A-3E show input object 300 (shown as
a finger) located in various locations in the capacitive sensing
region of first and second capacitive buttons 205 and 210,
respectively. The specific discussions regarding FIGS. 3A-3E refers
to using an absolute capacitance sensing scheme. However, it is
understood that similar results can be achieved using other sensing
schemes, including transcapacitive sensing schemes.
[0107] Although not shown in FIG. 3A, coupled with the first and
second capacitive buttons 205 and 210 is a controller, such as the
controller 105 of FIG. 2A. As previously noted, controller 105 can
be couple with or include activation identification mechanism 220
of FIG. 2A for interpreting electrode values to determine button
actuation.
[0108] Activation identification mechanism 220 is used to determine
activation status of sensor electrodes, and may be implemented as
circuitry, as software, or a combination thereof. In some
embodiments, a sensor electrode is considered to be active if its
associated electrode value is greater than or equal to an
activation threshold value, and inactive if its associated
electrode value is less than the activation threshold value.
Different sensor electrodes may have the same or different
activation threshold values.
[0109] In some embodiments, activation identification mechanism 220
may impose requirements such as particular trends of sensor
electrode values over time to switch the determined state of a
sensor electrode. For example, activation identification mechanism
220 may determine that a previously inactive sensor electrode is
active if its associated electrode values crossed its activation
threshold value in a particular way over time (e.g. increasing over
time from below to above the applicable threshold value, or vice
versa).
[0110] Further, some embodiments may impose "deactivation"
threshold values that differ from activation threshold values on
sensor electrodes considered to be in active states. Using
differing activation and deactivation threshold values introduces
hysteresis that may help "debounce" activation determinations. In
other words, having hysteresis helps prevent "fluttering" of
activation status for electrode values that are close to a
threshold, such that determinations of status would not quickly
swap between activated and inactivated states.
[0111] Similarly to activation threshold values, distinct sensor
electrodes may have the same or different deactivation threshold
values. The activation identification mechanism 220 may similarly
impose requirements for recognizing no activation such as
particular trends of sensor electrode values over time. For
example, activation identification mechanism 220 may determine that
a sensor electrode is inactive if its associated electrode values
crossed the applicable activation threshold value in a particular
way over time (e.g. decreasing over time from above to below the
applicable threshold value, or vice versa). The required activation
trends and the required deactivation trends can differ (e.g. differ
in direction, magnitude, etc.).
[0112] In some embodiments, activation statuses of sensor
electrodes have little or no effect on processing. For example, all
of the sensor electrodes may always be producing indicia at a set
frequency, processing may always be occurring at a constant rate,
or the like. In contrast, in some embodiments, activation status is
used to control processing such as sampling rate of indicia from
the sensor electrodes, generation of electrode values, calculation
of positional characteristics, determination of button actuations,
and the like. This approach can be used to save power by reducing
the amount of sampling or processing activity when there is no user
input to the capacitive buttons.
[0113] In some embodiments, at least some of the sensor electrodes
are not used to produce indicia, or at least some of the electrode
values that can be calculated are not, until after the activation
identification mechanism 220 provides one or more indications that
trigger such production. For example, the trigger can include that
at least one of the sensor electrodes is activated, that at least
some number of sensor electrodes are activated, that a select group
of sensor electrodes are activated, that at least some number of a
select group of sensor electrodes are activated, and the like.
[0114] Similarly, in some embodiments, the rate at which sensor
electrodes are used to produce indicia is slower until the
activation identification mechanism 220 provides one or more
indications that trigger a higher rate. Some other embodiments may
use indications from the activation identification mechanism 220 to
affect the rate at which electrode values are generated, which
sensor electrodes the electrode values are generated, which buttons
actuation status is determined for (if any), and the like.
[0115] In a simple embodiment, a capacitive button is determined to
be actuated when all of the sensor electrodes correlated with the
capacitive button are active.
[0116] Controller 105 can further couple with or include positional
characteristics analyzing unit 218 for determining button
actuation. In some embodiments, positional characteristics
analyzing unit 218 is configured to determine one or more
positional characteristics of one or more input objects with
respect to a capacitive button system. These positional
characteristics are then evaluated against various criteria for
gauging button actuation.
[0117] Some embodiments include disambiguating electrodes such as
disambiguating electrode 215 (shown in FIG. 2A). In such
embodiments, the controllers (e.g. controller 105 of FIG. 2A) may
also process the indicia from disambiguating electrodes to produce
disambiguating electrode values. The controllers may then use the
disambiguating electrode values in effecting button actuation. For
example, the controllers may reject or suppress potential button
actuations if the disambiguating electrode values indicate
something else aside from what appears to be a valid button press
(e.g. the presence of a relatively large object such as a palm of a
hand, a face, or other non-button input body part).
[0118] Referring now to FIG. 3A, a block diagram of first and
second capacitive buttons 205 and 210, respectively, is shown in
accordance with embodiments of the present technology. First
capacitive button 205 comprises sensor electrode elements A.sub.1,
B.sub.1 and C.sub.1 of sensor electrodes A, B, and C. Second
capacitive button 210 comprises sensor electrode elements A.sub.2,
B.sub.2, and D.sub.2 of sensor electrodes A, B, and D. Input object
300 (a finger is shown), is located at first position 305 over a
small portion of the right side of second capacitive button
210.
[0119] In such a case, the sensor electrodes A-D of the first and
second capacitive buttons 205 and 210 would provide indicia that
are received by a controller such as controller 105 of FIG. 2A. As
appropriate, controller 105 utilizes indicia received from sensor
electrodes A-D to generate electrode values, where at least three
electrode values are associated with each capacitive button (e.g.
capacitive buttons 205 and 210). As shown in FIG. 3A, first
capacitive button 205 and second capacitive button 210 share sensor
electrodes, thus electrode values are generated only for four
sensor electrodes A-D even though there are six sensor electrode
elements. Some of the same electrode values are correlated with
both capacitive buttons 205 and 210. The generated electrode values
are then utilized to determine button actuation status. This may
involve using the electrode values to determine positional
characteristics of the input object 300 in relation to first and
second capacitive buttons 205 and 210, respectively
[0120] Referring again to FIG. 3A, the input object 300 is located
at first position 305, above and "vertically" close to and directly
above a sliver of sensor electrode element A.sub.2 of second
capacitive button 210. In the discussion below, "vertical" is used
to describe the dimension into and out of the figure as drawn,
while "lateral" is used to describe the two dimensions that define
planes parallel to the figure as drawn.
[0121] The indicia provided by sensor electrodes A-D are reflective
of the effect of input object 300 on the amount of capacitive
coupling sensed by sensor electrodes A-D. Thus, the indicia
provided by sensor electrodes A-D would result in electrode values
reflective of the input object 300 being close to and directly
above a small portion of sensor electrode element A.sub.2 of second
capacitive button 210. In most embodiments, the indicia would
reflect changes in capacitive coupling with sensor electrode
element A.sub.2 due to the overlapping input object 300, and
perhaps smaller changes in capacitive coupling with sensor
electrode element D.sub.2 due to fringe capacitance. Controller 105
would process the received indicia and arrive at electrode values
that describe no input object overlapping with a small part of
sensor electrode A, close to sensor electrode D, and not close to
sensor electrodes B and C. In some embodiments, with such a set of
electrode values, controller 105 would determine that the input
object is somewhere near the right side of the second capacitive
button 210, since that is the location where a single input object
would be able to trigger such a set of electrode values. In some
embodiments, second capacitive button 210 would not be determined
to be actuated in such a case.
[0122] As discussed above, in some embodiments, the electrode
values generated for what is shown in FIG. 3A would likely indicate
that no activation thresholds have been satisfied. This result may
affect the sampling or the processing of data by the capacitive
sensing device. For example, in some embodiments, this may stop
processing of input or sampling at a slower rate. As another
example, in other embodiments, the electrode values generated for
what is shown in FIG. 3A may indicate interaction sufficient to
trigger further processing of input or to begin sampling at a
higher rate.
[0123] Referring now to FIG. 3B, a block diagram of capacitive
buttons is shown in accordance with embodiments of the present
technology. First and second capacitive buttons 205 and 210 are
shown with input object 300 at a second position 310 over the
entire set of sensor electrode elements A.sub.2, B.sub.2, and
D.sub.2 of second capacitive button 210. Sensor electrode elements
A.sub.2, B.sub.2, and D.sub.2 are parts of sensor electrodes A, B,
and D, respectively. The sensor electrodes A-D provide indicia
relating to input object 300 at second position 310, which reflects
input object 300 interacting with sensor electrodes A, B, and D.
Controller 105 utilizes the indicia from sensor electrodes A-D to
generate the electrode values usable for gauging button
actuation.
[0124] In many embodiments, activation identification mechanism 220
would indicate that activation threshold values for the sensor
electrodes A, B, and D have been exceeded in a case as shown in
FIG. 3B. Since A-B-D is a valid capacitive button combination (that
of second capacitive button 210), a simple implementation may
determine that second capacitive button 210 is actuated based only
on these values.
[0125] More complex implementations may examine one or more
positional characteristics determined by a positional
characteristics analyzing unit 218 to determine button actuation.
These more complex implementations would determine and evaluate if
select positional characteristics meet particular criteria required
for actuating second capacitive button 210. For example, some
embodiments may pose requirements on the prior location(s) of the
input object 300. In some embodiments, if input object 300 moved in
toward the button laterally (e.g. from position 305) before
reaching second position 310, then controller 105 may not recognize
a button actuation. However, if input object 300 arrived in
vertically to position 310 without much lateral movement, the
controller 105 may recognize a button actuation.
[0126] Continuing now with FIG. 3C, a block diagram of capacitive
buttons is shown in accordance with embodiments of the present
technology. First and second capacitive buttons 205 and 210,
respectively, are shown with input object 300 at a third position
315 over a left portion of sensor electrode elements A.sub.2,
B.sub.2, and D.sub.2 of second capacitive button 210. Specifically,
input object 300 of FIG. 3C is disposed close to and covers
portions of sensor electrode elements B.sub.2, and D.sub.2 of
sensor electrodes B and D. The indicia provided by sensor
electrodes A-D provide reflect input object 300 at third position
315, which reflects input object 300 interacting mostly with sensor
electrodes B and D.
[0127] Third position 315 places the input object 300 a bit
off-center over sensor electrode element B.sub.2 of second
capacitive button 210. This means that the resulting indicia and
electrode values would reflect a relatively larger amount of user
interaction with sensor electrode B and a relatively lesser amount
of user interaction with sensor electrode D. In some embodiments,
sensor electrode A results may also be slightly affected due to
fringing effects (although such effects are likely to be minimal)
and sensor electrode C results are not significantly affected.
[0128] In many embodiments, actuation identification mechanism 220
would indicate that sensor electrodes B and perhaps D are
activated, and second capacitive button 210 would not be determined
to be actuated. Controller 105 may determine no button actuation
independent of prior interaction by input object 300 with first and
second capacitive buttons 205 and 210 (e.g. independent of how
input object 300 reached third position 315).
[0129] Continuing now with FIG. 3D, a block diagram of capacitive
buttons is shown in accordance with embodiments of the present
technology. First and second capacitive buttons 205 and 210,
respectively, are shown with input object 300 at a fourth position
320 between first and second capacitive buttons 205 and 210. Input
object 300 of FIG. 3D is not near any portions of first and second
capacitive buttons 205 and 210. Hence, indicia from sensor
electrodes A-D would reflect such, and no button actuation
results.
[0130] It is worth noting that input object 300 in fourth position
320 overlaps with the routing traces of all four sensor electrodes
A-D. Thus, it may be possible for input object 300 to interact
capacitively with the routing traces, affect the indicia generated
by sensor electrodes A-D, and cause incorrect button actuations. In
most embodiments, this potential problem can be addressed by
positioning the routing traces farther away from the input object
300 in the third dimension (into and out of the page in FIG. 3D),
by proper shielding of the routing traces, by disposing the routing
traces elsewhere (e.g. in areas that input objects are unlikely to
be near), minimizing the area available for capacitive coupling, a
combination thereof, or the like.
[0131] Referring now with FIG. 3E, a block diagram of capacitive
buttons is shown in accordance with embodiments of the present
technology. First and second capacitive buttons 205 and 210,
respectively, are shown, with input object 300 at a fifth position
325 over first capacitive button 205.
[0132] Input object 300 of FIG. 3E is positioned over a right
portion of the sensor electrode elements A.sub.1, B.sub.1 and
C.sub.1 of first capacitive button 205, and covers portions of
sensor electrode elements B.sub.1 and C.sub.1 of sensor electrodes
B and C. The sensor electrodes A-D provide indicia relating to
input object 300 at fifth position 325, which reflects input object
300 interacting mostly with sensor electrodes B and C. In many
embodiments, the change in capacitive coupling is sufficient to
cause sensor electrode B, and perhaps sensor electrode C, to be
activated. In some embodiments, sensor electrode A results may also
be slightly affected due to fringing effects (although such effects
are likely to be minimal) and sensor electrode D results are not
significantly affected. In many embodiments, with such a set of
indicia and resulting sensor electrode values, no button actuation
is recognized.
[0133] Referring now to FIG. 3F, a block diagram of capacitive
buttons is shown in accordance with embodiments of the present
technology. First and second capacitive buttons 205 and 210,
respectively, are shown with input objects 340 and 345 (fingers are
shown) concurrently disposed in sensing region of capacitive
buttons 205 and 210. Input object 340, at sixth position 330,
overlaps sensor electrode elements B.sub.1 and C.sub.1 of sensor
electrodes B and C. Input object 345, at seventh position 335,
covers an entire set of sensor electrode elements (that of second
capacitive button 210). In other words, input object 345 is close
to and overlaps sensor electrode elements A.sub.2, B.sub.2, and
D.sub.2 of sensor electrodes A, B, and D With a case such as what
is shown in FIG. 3F, the resulting indicia typically indicates user
interaction with all four sensor electrodes A-D.
[0134] In many embodiments, this would result in all of the sensor
electrodes A-D activated. In some embodiments, the controller may
suppress or reject all button actuation possibilities, since having
all sensor electrodes A-D activated may cause ambiguity about
whether the user intended to actuate either or both of capacitive
buttons 205 and 210. This is especially likely if the input objects
340 and 345 arrived substantially simultaneously in sixth position
330 and seventh position 335.
[0135] If the arrival of input objects 340 and 345 in sixth
position 330 and seventh position 335 are sufficiently separated in
time, then button actuation may have occurred earlier. In many
embodiments, if input object 345 arrives at seventh position 335
substantially before the arrival of input object 340 at sixth
position 330, then input object 345 may have caused actuation of
second capacitive button 210 before input object 340 arrived at
sixth position 330. However, in many embodiments, if input object
345 arrives at seventh position 335 substantially after the arrival
of input object 340 at sixth position 330, then input object 345
may not have caused actuation of second capacitive button 210.
[0136] Further, in many embodiments, input object 340 would not
cause actuation of first capacitive button 205 regardless of if
input object 340 arrives at sixth position 330 before, after, or at
the same time as input object 345 arriving at seventh position 335.
In those embodiments, the interaction of input object 340, at sixth
position 330, with first capacitive button 205 is not sufficient to
result in actuation of first capacitive button 205.
[0137] Some embodiments may recognize that sensor electrodes B and
perhaps C are experiencing an amount of interaction indicative of
user input interacting with more than one sensor electrode element
of the respective sensor electrodes. In such embodiments, the
controller may suppress, reject, or ignore button actuation
possibilities since such amounts of interaction may cause ambiguity
about whether the user intended to actuate either or both of the
capacitive buttons 205 and 210.
[0138] It should be noted that there would be less ambiguity for a
scenario such as shown in FIG. 3F if sensor electrodes were not
shared between first and second capacitive buttons 205 and 210. If
sensor electrodes were not shared, and six distinct sensor
electrodes are used (one for each sensor electrode element), then
the indicia from the sensor electrodes would indicate that an input
object is over part of first capacitive button 205 (not centered)
and a second input object is over the second capacitive button 210
(likely centered). In such a case, the controller may allow
actuation of the second capacitive button 210.
[0139] Of note, the present technology may also be utilized in
conjunction with haptic feedback. A haptic feedback mechanism may
be used to provide haptic feedback in response to activation of one
or more sensor electrodes. Alternatively or in addition to
providing feedback in response to sensor electrode activation,
haptic feedback may be provided in response to button actuation.
The timing of feedback may be provided on the "press" of a
capacitive button, on the "release" of a capacitive button, or
both. Also, different haptic feedback may be provided for
activation of a sensor electrode vs. actuation of a button, for
activation of different sensor electrodes, for actuation of
different capacitive buttons, for press versus release, for
suppressed button actuation (e.g. suppression in response to
indicia from one or more disambiguating electrodes or other
inputs), and the like. For example, the haptic feedback may be
continuous or pulsed, or otherwise vary in magnitude or frequency.
Haptic feedback may also be used in combination with other types of
feedback, including visual and auditory feedback.
[0140] FIG. 9 is a flow diagram 900 of a method for determining
actuation of a capacitive button, according to one embodiment.
Thus, although flow diagram 900 shows three steps in a particular
order, it is understood that different implementations may include
different numbers of steps in other orders. Reference will be made
to the capacitive sensing device 100 of FIGS. 1 and 2 in the
description of flow diagram 900 in the discussion below for
convenience. It is understood that the steps described below may be
used with any of the different MSE capacitive button systems
described herein.
[0141] In 905, in one embodiment, the method receives indicia from
at least three distinct sensor electrodes comprising a capacitive
button. In some implementations, this involves driving sensor
electrodes to measure the amount of capacitive coupling of the
sensor electrodes to an external object.
[0142] In some other implementations, 905 may involve emitting
electrical signals using an emitter sensor electrode that is
separate from the at least three distinct sensor electrodes. The
electrical signals would be configured for effecting receipt of the
indicia from the at least three distinct sensor electrodes.
[0143] In yet other implementations, 905 may involve emitting
electrical signals using at least two of the at least three
distinct sensor electrodes. As discussed above, using the same
sensor electrodes to emit and receive means that the capacitive
sensing device will likely time multiplex between different
emitter-receiver combinations. The electrical signals emitted by
the at least two of the at least three distinct sensor electrodes
would be configured for effecting receipt of the indicia from the
at least three distinct sensor electrodes.
[0144] In 910, in one embodiment, the method generates at least
three electrode values from the indicia received from the at least
three sensor electrodes.
[0145] In 915, in one embodiment, the method utilizes the at least
three electrode values to determine actuation of the capacitive
button. Actuation determination in 915 can involve direct
examination of the electrode values themselves, such as by
comparing at least one of the electrode values to an activation
threshold value. For example, this can be done with an activation
identification mechanism 220 that can indicate when indicia
received from particular sensor electrodes exceed one or more
activation thresholds, as discussed above. Further, the temporal
characteristics of the electrode values may also be evaluated in
determining button actuation.
[0146] Alternatively, actuation determination in 915 can involve
indirect examination of the electrode values by calculating
positional characteristics, such as with a positional
characteristics analyzing unit 218. For example, actuation
determination may involve determining one or more position
characteristics of one or more input objects with respect to the
capacitive button. The positional characteristics may be determined
for an instance in time or over a span of time. For example,
position may be estimated using the electrode values.
[0147] Further, actuation determination in 915 can involve a
combination of the approaches described above. For example,
embodiments may use any combination of examining electrode values
directly, evaluate changes to electrode values over time, determine
and examine positional characteristics, evaluate temporal changes
to positional characteristics, and the like.
[0148] As discussed above, the number and order of the parts of
flow diagram 900 can change in specific implementations. For
example, one or more additional blocks can be added to support
distinguishing false actuations using a disambiguating electrode.
Specifically, the capacitive sensing device 100 can include one or
more disambiguating electrodes disposed proximate to the capacitive
button, and the flow diagram 900 can include receiving indicia from
such disambiguating electrode(s). The flow diagram 900 can further
include generating one or more disambiguating values from the
indicia received from the disambiguating electrode(s), and
utilizing the disambiguating value(s) to determine a false
actuation of the capacitive button.
[0149] As another example, the capacitive sensing device 100 can be
configured to effect haptic feedback by directly controlling a
haptic feedback system, or by providing an indication that haptic
feedback should be provided. Flow diagram 900 can then be expanded
to include effecting haptic feedback in response to a determination
of button actuation.
[0150] Electronic systems can include and operate with MSE
capacitive buttons. For example, an electronic system can include
an output device capable of providing human-observable output, a
plurality of capacitive buttons, and a controller. The plurality of
capacitive buttons includes a substrate, a first set of sensor
electrode elements disposed on the substrate, and a second set of
sensor electrode elements disposed on the substrate. The first set
of sensor electrode elements has at least three sensor electrode
elements associated with distinct sensor electrodes of a plurality
of sensor electrodes; that is, at least three sensor electrode
elements of the first set do not share sensor electrodes with each
other (however, if there are more than three sensor electrode
elements in the first set, they may share sensor electrodes in some
cases). Similarly, the second set of sensor electrode elements also
has at least three sensor electrode elements that do not share
sensor electrodes with each other. In some embodiments, one or more
sensor electrode elements of the first set may be associated with
the same sensor electrode(s) as one or more sensor electrode
element of the second set. That is, the first and second sets of
sensor electrode elements may share sensor electrodes.
[0151] The controller is coupled to the plurality of capacitive
buttons and is configured to receive indicia from the plurality of
sensor electrodes, to generate at least three electrode values
using the indicia received from sensor electrodes associated with
the first set of sensor electrode elements, and to utilize the at
least three electrode values to determine actuation of the first
capacitive button.
[0152] The controller is further configured to effect
human-observable output using the output device in response to
actuation of the capacitive button. This can be done by controlling
the output device, or indirectly by indicating to some other device
that the output device should provide human-observable output.
[0153] The output device can be any appropriate device that outputs
something observable by human senses such as sight, hearing, smell,
taste, and touch. For example, the output device may provide visual
output, auditory output, kinesthetic output, or a combination
thereof. In some embodiments, the output device is a sound device,
and the controller causes one or more sounds using the sound
device. In other embodiments, the output device is a force feedback
device, and the controller causes haptic feedback using the force
feedback device.
[0154] The foregoing descriptions of specific embodiments have been
presented for purposes of illustration and description. They are
not intended to be exhaustive or to limit the present technology 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 present technology and its practical application,
to thereby enable others skilled in the art to best utilize the
present technology and various embodiments with various
modifications as are suited to the particular use contemplated. It
is intended that the scope of the present technology be defined by
the claims appended hereto and their equivalents.
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