U.S. patent application number 12/242772 was filed with the patent office on 2009-07-09 for selective rejection of touch contacts in an edge region of a touch surface.
Invention is credited to Wayne Carl WESTERMAN.
Application Number | 20090174679 12/242772 |
Document ID | / |
Family ID | 40343772 |
Filed Date | 2009-07-09 |
United States Patent
Application |
20090174679 |
Kind Code |
A1 |
WESTERMAN; Wayne Carl |
July 9, 2009 |
Selective Rejection of Touch Contacts in an Edge Region of a Touch
Surface
Abstract
The selective rejection of touch contacts in an edge region of a
touch sensor panel is disclosed. In addition, by providing certain
exceptions to the rejection of edge contacts, the functionality of
the touch sensor panel can be maximized. Contacts in edge bands
around the perimeter of a touch sensor panel can be ignored.
However, if a contact in the edge band moves beyond a threshold
distance or speed, it can be recognized as part of a gesture. To
accommodate different finger sizes, the size of the edge band can
be modified based on the identification of the finger or thumb.
Furthermore, if contacts in the center region of a touch sensor
panel track the movement of contacts in the edge band, the contacts
in the edge band can be recognized as part of a gesture.
Inventors: |
WESTERMAN; Wayne Carl; (San
Francisco, CA) |
Correspondence
Address: |
APPLE C/O MORRISON AND FOERSTER ,LLP;LOS ANGELES
555 WEST FIFTH STREET SUITE 3500
LOS ANGELES
CA
90013-1024
US
|
Family ID: |
40343772 |
Appl. No.: |
12/242772 |
Filed: |
September 30, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61019220 |
Jan 4, 2008 |
|
|
|
Current U.S.
Class: |
345/173 |
Current CPC
Class: |
G06F 2203/04808
20130101; G06F 3/04883 20130101; G06F 3/04186 20190501; G06F
2203/04106 20130101; G06F 3/03547 20130101; G06F 3/0488 20130101;
G06F 2203/04105 20130101; G06F 3/04886 20130101; G06F 3/0418
20130101; G06F 2203/04104 20130101; G06F 3/0416 20130101; G06F
3/044 20130101 |
Class at
Publication: |
345/173 |
International
Class: |
G06F 3/041 20060101
G06F003/041 |
Claims
1. A method for selectively rejecting contacts on a touch sensor
panel, comprising: designating one or more regions in the touch
sensor panel as contact rejection regions; and selectively
rejecting or recognizing a first contact detected within the one or
more contact rejection regions in accordance with rejection or
recognition criteria.
2. The method of claim 1, further comprising recognizing the first
contact if a second contact is also detected within a main region
of the touch sensor panel.
3. The method of claim 1, further comprising recognizing the first
contact if a second contact is also detected within a main region
of the touch sensor panel and the first contact is detected as
having movement exceeding a particular threshold.
4. The method of claim 1, further comprising recognizing the first
contact only if the first contact is recognized as a part or all of
particular gesture.
5. The method of claim 1, further comprising varying a size of the
contact rejection region in accordance with an identification of a
finger or thumb as a cause of the first contact.
6. The method of claim 1, further comprising recognizing the first
contact if a second contact is also detected within a main region
of the touch sensor panel and the first and second contacts have
substantially synchronous movement.
7. The method of claim 1, further comprising recognizing the first
contact as part of a gesture if one or more second contacts are
detected within a main region of the touch sensor panel as being
part of the gesture.
8. The method of claim 7, further comprising recognizing the one or
more second contacts as part of a drag gesture and the first
contact as being a drag lock component of the drag gesture.
9. The method of claim 1, further comprising recognizing the first
contact as changing a first gesture if one or more second contacts
performing the first gesture are detected within a main region of
the touch sensor panel.
10. The method of claim 1, further comprising varying a size of the
contact rejection region in accordance with a computed parameter of
the first contact.
11. The method of claim 1, further comprising designating contact
rejection regions along a perimeter of the touch sensor panel.
12. The method of claim 11, further comprising assigning different
widths to the contact rejection regions along various edges of the
touch sensor panel.
13. The method of claim 1, further comprising recognizing the first
contact if a second contact is also detected within a particular
predetermined distance range from the first contact.
14. The method of claim 1, further comprising recognizing the first
contact if a second contact is also detected within a main region
of the touch sensor panel and the first and second contacts touch
down at substantially the same time.
15. A computer-readable storage medium storing program code for
selectively rejecting contacts on a touch sensor panel, the program
code for causing performance of a method comprising: selectively
rejecting or recognizing a first contact detected in one or more
designated contact rejection regions in the touch sensor panel in
accordance with rejection or recognition criteria; wherein the one
or more contact rejection regions are located along one or more
edges of the touch sensor panel.
16. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact if a second contact
is also detected within a main region of the touch sensor
panel.
17. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact if a second contact
is also detected within a main region of the touch sensor panel and
the first contact is detected as having movement exceeding a
particular threshold.
18. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact only if the first
contact is recognized as a part or all of particular gesture.
19. The computer-readable storage medium of claim 15, the program
code further for varying a size of the contact rejection region in
accordance with an identification of a finger or thumb as a cause
of the first contact.
20. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact if a second contact
is also detected within a main region of the touch sensor panel and
the first and second contacts have substantially synchronous
movement.
21. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact as part of a gesture
if one or more second contacts are detected within a main region of
the touch sensor panel as being part of the gesture.
22. The computer-readable storage medium of claim 21, the program
code further for recognizing the one or more second contacts as
part of a drag gesture and the first contact as being a drag lock
component of the drag gesture.
23. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact as changing a first
gesture if one or more second contacts performing the first gesture
are detected within a main region of the touch sensor panel.
24. The computer-readable storage medium of claim 15, the program
code further for varying a size of the contact rejection region in
accordance with a computed parameter of the first contact.
25. The computer-readable storage medium of claim 15, the program
code further for designating contact rejection regions along a
perimeter of the touch sensor panel.
26. The computer-readable storage medium of claim 25, the program
code further for assigning different widths to the contact
rejection regions along various edges of the touch sensor
panel.
27. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact if a second contact
is also detected within a particular predetermined distance range
from the first contact.
28. The computer-readable storage medium of claim 15, the program
code further for recognizing the first contact if a second contact
is also detected within a main region of the touch sensor panel and
the first and second contacts touch down at substantially the same
time.
29. A mobile telephone including computer-readable storage medium
storing program code for selectively rejecting contacts on a touch
sensor panel, the program code for causing performance of a method
comprising: selectively rejecting or recognizing a first contact
detected in one or more designated contact rejection regions in the
touch sensor panel in accordance with rejection or recognition
criteria; wherein the one or more contact rejection regions are
located along one or more edges of the touch sensor panel.
30. A media player including computer-readable storage medium
storing program code for selectively rejecting contacts on a touch
sensor panel, the program code for causing performance of a method
comprising: selectively rejecting or recognizing a first contact
detected in one or more designated contact rejection regions in the
touch sensor panel in accordance with rejection or recognition
criteria; wherein the one or more contact rejection regions are
located along one or more edges of the touch sensor panel.
31. A personal computer including computer-readable storage medium
storing program code for selectively rejecting contacts on a touch
sensor panel, the program code for causing performance of a method
comprising: selectively rejecting or recognizing a first contact
detected in one or more designated contact rejection regions in the
touch sensor panel in accordance with rejection or recognition
criteria; wherein the one or more contact rejection regions are
located along one or more edges of the touch sensor panel.
32. A method for interpreting contacts on a touch sensor panel,
comprising: designating one or more regions in the touch sensor
panel as click regions; detecting a mechanical click of the touch
sensor panel; detecting a touch at a particular click region at
about a same time as the detection of the mechanical click; and
interpreting the touch in accordance with the particular click
region.
33. The method of claim 32, further comprising allocating an area
of one or more of the click regions in accordance with button usage
patterns.
34. The method of claim 32, further comprising allocating a
location of one or more of the click regions in accordance with
button usage patterns.
35. The method of claim 32, further comprising dynamically
designating the one or more click regions in accordance with
current device usage.
36. A computer-readable storage medium storing program code for
interpreting contacts on a touch sensor panel, the program code for
causing performance of a method comprising: detecting a mechanical
click from a touch sensor panel capable of producing the mechanical
click by applying pressure anywhere on the touch sensor panel; and
interpreting a touch detected at a particular click region on the
touch sensor panel at about a same time as the mechanical click of
the touch sensor panel is detected in accordance with the
particular click region.
37. The computer-readable storage medium of claim 36, the program
code further for allocating an area of one or more click regions in
accordance with button usage patterns.
38. The computer-readable storage medium of claim 36, the program
code further for allocating a location of one or more click regions
in accordance with button usage patterns.
39. The computer-readable storage medium of claim 36, the program
code further for dynamically designating the one or more click
regions in accordance with current device usage.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 61/019,220 filed on Jan. 4, 2008, the
contents of which are incorporated herein by reference in their
entirety for all purposes.
FIELD OF THE INVENTION
[0002] This relates generally to input devices for computing
systems, and more particularly, to the selective rejection of touch
contacts in an edge region of a touch sensor panel.
BACKGROUND OF THE INVENTION
[0003] Many types of input devices are presently available for
performing operations in a computing system, such as buttons or
keys, mice, trackballs, touch sensor panels, joysticks, touch
screens and the like. Touch screens, in particular, are becoming
increasingly popular because of their ease and versatility of
operation as well as their declining price. Touch screens can
include a touch sensor panel, which can be a clear panel with a
touch-sensitive surface. The touch sensor panel can be positioned
in front of a display screen so that the touch-sensitive surface
covers the viewable area of the display screen. Touch screens can
allow a user to make selections and move a cursor by simply
touching the display screen via a finger or stylus. In general, the
touch screen can recognize the touch and position of the touch on
the display screen, and the computing system can interpret the
touch and thereafter perform an action based on the touch
event.
[0004] Touch sensor panels can be implemented as an array of pixels
formed by multiple drive lines (e.g. rows) crossing over multiple
sense lines (e.g. columns), where the drive and sense lines are
separated by a dielectric material. An example of such a touch
sensor panel is described in Applicant's co-pending U.S.
application Ser. No. 11/650,049 entitled "Double-Sided Touch
Sensitive Panel and Flex Circuit Bonding," filed on Jan. 3, 2007,
the contents of which are incorporated by reference herein.
[0005] However, fingers and palms inadvertently in close proximity
with a touch sensor panel can cause unintended gestures to be
recognized and processed. These inadvertent touches can often occur
when the touch sensor panel is separate from but adjacent to other
input devices being used, such as a conventional keyboard or
mechanical buttons or bars. Additionally, when the touch sensor
panel itself is being used, fingers such as those used for
stabilization of the hand (but not part of the gesture) or holding
the device can accidentally touch the edges of the panel and be
detected.
SUMMARY OF THE INVENTION
[0006] This relates to the selective rejection of touch contacts
(touch events) in an edge region of a touch sensor panel to
minimize unintended operations. In addition, by providing certain
exceptions to the rejection of edge contacts, the functionality of
the touch sensor panel can be maximized.
[0007] In some embodiments, contacts in edge bands around the
perimeter of a touch sensor panel can simply be ignored. However,
there can be a number of exceptions to edge rejection. For example,
contacts in both the center area and the edge band can cause the
contact in the edge band to be recognized as part of a gesture in
certain circumstances. In other embodiments, if the contact in the
edge band is stationary, it can be ignored. However if the contact
in the edge band moves beyond a threshold distance or speed, it can
then be recognized as part of a gesture.
[0008] Similarly, in trackpad embodiments, contacts within a bottom
region of the trackpad can be ignored if stationary, but recognized
as part of a gesture if moving. To accommodate different finger
sizes, the size of one or more regions (e.g. the bottom or top
region) can be modified based on an identification of the finger or
thumb.
[0009] If contacts in the center or main region of a touch sensor
panel track the movement of contacts in the edge band or bottom
region, the contacts in the edge band or bottom region may not be
ignored, but instead be recognized as part of a gesture. In
addition, contacts appearing in the edge band or bottom region
during the recognition of gestures in the center or main regions of
a touch sensor panel can be recognized as part of the gesture or as
a control input to implement operations such as drag lock or
conversion of gestures. In other embodiments, two or more contacts
detected in an edge band can be interpreted as a gesture if the
contacts have a certain predetermined spacing (e.g., their
centroids have an x-direction separation of between 1-3 cm).
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1a illustrates an exemplary touch sensor panel
implementing edge rejection according to one embodiment of this
invention.
[0011] FIG. 1b illustrates an exemplary touch sensor panel
implementing an exception to edge rejection according to one
embodiment of this invention.
[0012] FIG. 2 illustrates an exemplary trackpad implementing edge
rejection according to one embodiment of this invention.
[0013] FIG. 3a illustrates an exemplary touch sensor panel
implementing edge rejection and exceptions to edge rejection
according to one embodiment of this invention.
[0014] FIG. 3b illustrates an exemplary touch sensor panel
implementing edge rejection exceptions based on the recognition of
two contacts having synchronized movements according to one
embodiment of this invention.
[0015] FIG. 4 illustrates an exemplary touch sensor panel
implementing exceptions to edge rejection in order to provide a
drag lock function according to one embodiment of this
invention.
[0016] FIG. 5a illustrates an exemplary touch sensor panel
implementing exceptions to edge rejection based on contacts in an
edge region and a main region according to one embodiment of this
invention.
[0017] FIG. 5b illustrates an exemplary touch sensor panel
implementing exceptions to edge rejection in order to allow a
pinching gesture according to one embodiment of this invention.
[0018] FIGS. 5c and 5d illustrate an exemplary exception to edge
rejection and an example of edge rejection, respectively, according
to embodiments of the invention.
[0019] FIG. 6 illustrates an exemplary touch sensor panel employing
edge rejection with a variable width edge band according to one
embodiment of this invention.
[0020] FIG. 7a illustrates an exemplary trackpad 700 having an
integrated pick button and click regions according to embodiments
of the invention.
[0021] FIG. 7b illustrates an exemplary extension of the embodiment
of FIG. 7a in which more than two click regions can be defined
according to embodiments of the invention.
[0022] FIG. 8 illustrates an exemplary computing system operable
with a touch sensor panel to implement edge rejection and
exceptions to edge rejection according to one embodiment of this
invention.
[0023] FIG. 9a illustrates an exemplary mobile telephone that can
include a touch sensor panel and computing system for implementing
edge rejection and exceptions to edge rejection according to one
embodiment of this invention.
[0024] FIG. 9b illustrates an exemplary digital media player that
can include a touch sensor panel and computing system for
implementing edge rejection and exceptions to edge rejection
according to one embodiment of this invention.
[0025] FIG. 9c illustrates an exemplary personal computer that can
include a touch sensor panel and computing system for implementing
edge rejection and exceptions to edge rejection according to one
embodiment of this invention.
[0026] FIG. 10 is a simplified diagram of an exemplary touch pad
and display according to one embodiment of this invention.
[0027] FIG. 11 is a perspective view of an exemplary input device
according to one embodiment of this invention.
[0028] FIGS. 12A, 12B, 12C and 12D are simplified side views of an
exemplary input device having a button touch pad according to one
embodiment of this invention.
[0029] FIG. 13 is a simplified block diagram of an exemplary input
device connected to a computing device according to one embodiment
of this invention.
[0030] FIG. 14 is a side view, in cross section, of an exemplary
input device according to one embodiment of this invention.
[0031] FIG. 15 is another side view, in cross section, of the
exemplary input device of FIG. 12 according to one embodiment of
this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] In the following description of preferred embodiments,
reference is made to the accompanying drawings in which it is shown
by way of illustration specific embodiments in which the invention
can be practiced. It is to be understood that other embodiments can
be used and structural changes can be made without departing from
the scope of the embodiments of this invention.
[0033] This relates to the selective rejection of touch contacts in
an edge region of a touch sensor panel to minimize unintended
operations. In addition, by providing certain exceptions to the
rejection of edge contacts, the functionality of the touch sensor
panel can be maximized.
[0034] FIG. 1a illustrates exemplary touch sensor panel 100
implementing edge rejection according to embodiments of the
invention. Edge band 102 (contact rejection region) can be created
in an outer boundary of touch sensor panel 100, surrounding center
area 104. If all contacts (e.g. fingers or palms) are detected in
edge band 102, the contacts can be ignored. In the example of FIG.
1a, because touch images 106 and 108 have centroids 110 and 112,
respectively, located in edge band 102, the contacts can be
ignored.
[0035] FIG. 1b illustrates a second scenario that can occur on
exemplary touch sensor panel 100 according to embodiments of the
invention. In the example of FIG. 1b, if contact 114 is detected in
center area 104 along with contact 116 in edge band 102, a contact
can be recognized in both the center area and the edge band. The
recognition of the edge contact in this scenario in accordance with
the aforementioned criteria (rejection or recognition criteria) can
prevent intended gestures such as pinching gestures with contacts
starting in an edge band from being ignored.
[0036] However, when fingers are used to perform an operation such
as pointing in center area 104, a so-called "pinky" or other finger
inadvertently placed in edge band 102 can be recognized, and an
unintended gesture can be performed instead of the pointing
gesture. Therefore, in other embodiments of the invention, if
contacts 114 and 116 are detected at both center area 104 and edge
band 102, and if centroid 118 of edge contact 116 does not move
more than a threshold amount (e.g. 1 mm), it can be ignored.
However, if edge contact 116 moves more than the threshold amount
in any direction (even if there is no other finger detected in the
center area), it can be recognized and become a trackable contact
that can be part of a gesture. This recognition also allows for
tracking operations to be performed within edge band 102.
[0037] FIG. 2 illustrates an exemplary touch sensor panel in the
form of trackpad 200 implementing edge rejection according to
embodiments of the invention. In the example of FIG. 2, adjacent to
trackpad 200 is a conventional keyboard space bar 202 and
mechanical pick button 204. Exemplary inadvertent touches
illustrated in FIG. 2 can include thumb 206 resting on space bar
202 but also inadvertently resting on trackpad 200. The detected
contact at 208 can be ignored so that clicks or other actions are
not accidentally generated. In addition, pinky 210 inadvertently
touching trackpad 200 can be ignored, and thumb 212 resting on pick
button 204 but also overhanging the bottom of the trackpad at 214
can be ignored to avoid it being recognized as part of an
unintended pinch gesture.
[0038] FIG. 3a illustrates another exemplary touch sensor panel 300
implementing edge rejection according to embodiments of the
invention. In the example of FIG. 3a, touch sensor panel 300 can
include a bottom region 302 that can normally be reserved for
performing certain non-gesture actions. For example, finger taps in
bottom region 302 can be interpreted as a "click" or selection
function. Thus, contacts in bottom region 302 can normally be
ignored for all purposes except these functions. Nevertheless, it
can be desirable to have contacts in bottom region 302 recognized
as part of a gesture in certain circumstances. Therefore, according
to some embodiments of the invention, in accordance with rejection
or recognition criteria, contacts 304 identified as a finger (i.e.
a non-concentric image of touch of a certain threshold size)
occurring within the bottom region can be ignored if centroid 306
is stationary, but can be recognized as part of a gesture if the
centroid is not stationary. Identification of touch events is
disclosed in U.S. Pat. No. 6,323,846 entitled "Method and Apparatus
for Integrating Manual Input," the contents of which are
incorporated herein by reference in its entirety for all purposes.
Stationary, as defined herein, is when the centroid moves less than
a threshold amount from a computed centroid center, or remains
below some speed threshold. If the difference between an
instantaneous position and a low pass filter (LPF) averaged
position value exceeds a certain threshold value, the centroid can
be considered in motion and no longer stationary. Using this
criteria, contacts with slow drifting or rolling motions can be
ignored, but faster drifts can cause the contact to be recognized
as part of a gesture.
[0039] In another embodiment of the invention, the size of bottom
region 302 or top region 316 (or any other edge region) can
dynamically change based on a determination that a contact was
caused by a particular finger. For example, if a thumb is detected
in bottom region 302, then based on the radius of the touch area,
demarcation line 308 defining the bottom region can be moved upward
to increase the size of the bottom region. However, if a finger is
detected in bottom region 302, demarcation line 308 can be moved
downward to decrease the size of the bottom region. Similar
adjustments can be made for the top region 316, or any other edge
regions (e.g. left or right side regions).
[0040] As described above, contacts in bottom region 302 can be
treated as non-contacts independent from main region 310, although
in some embodiments contacts in the bottom region can be detected
and used in conjunction with contacts in the main area. For
example, if the contacts in bottom region 302 move in a manner that
is synchronous with or otherwise associated with movements in main
region 310, the contacts in the bottom region can be recognized
along with the contacts in the main region as part of the
gesture.
[0041] FIG. 3b illustrates the recognition of two contacts having
synchronized movements according to embodiments of the invention.
In the example of FIG. 3b, if contacts 304 and 312 move in a
substantially synchronous manner with respect to each other,
contact 304 can be recognized along with contact 312 as part of a
gesture. Otherwise, contact 304 can be ignored. Two contacts moving
"synchronously," as defined herein, can include centroids moving at
approximately the same speed and/or direction (either X and Y
components together, or only the X or only the Y components). In
other embodiments, the synchronized movements of two contacts can
include touching down synchronously. Thus, even though one of the
two contacts may touch down within an edge band, if it touches down
at substantially the same time as a contact touching down in the
main region 310, the two contacts can be recognized as part of a
gesture.
[0042] FIG. 4 illustrates another exemplary exception to edge
rejection according to embodiments of the invention. In the example
of FIG. 4, at location (1), contacts 416 and 418 caused by two
fingers within main region 410 move to the left as part of an
intended drag operation. At location (2), contacts 416 and 418 have
reached the leftmost edge of main region 410. If the drag operation
is to continue, at location (3) a thumb can be placed down in
bottom region 402, causing contact 420 to appear, In this
embodiment, instead of being ignored, the two preexisting contacts
416 and 418 cause contact 420 to be recognized as a so-called "drag
lock" feature of the gesture. With the drag lock in place, the two
fingers can be temporarily lifted off the touch sensor panel and
touched down again towards the center of main region 410 at
location (4), where the leftward drag operation can continue. It
should be understood that this edge rejection exception can also be
applied to other gestures in main region 410, wherein other
contacts in the main region, optionally accompanied by movement,
can cause subsequent contacts in bottom region 402 to be recognized
as part of a gesture. Alternatively, the subsequent contact in
bottom region 402 can cause a change in the gesture recognized in
main region 410. For example, a pointing function in main region
410 can be converted to a drag function as soon as a contact is
either detected in, or removed from, bottom region 402.
[0043] FIG. 5a illustrates another exemplary exception to edge
rejection according to embodiments of the invention. In FIG. 5a,
stationary thumb 524 detected in bottom region 502 plus finger 522
detected in main region 510 can be recognized as the start of a
finger drag gesture, and can remain so as long as the finger moves
while the thumb remains stationary.
[0044] FIG. 5b illustrates yet another exemplary exception to edge
rejection according to embodiments of the invention. In FIG. 5b,
thumb 524 detected in bottom region plus finger 522 detected in
main region 510 moving simultaneously towards each other can be
recognized as the start of a pinch gesture.
[0045] FIG. 5c illustrates another exemplary exception to edge
rejection according to embodiments of the invention. In FIG. 5c,
two or more contacts 528 detected in an edge band (e.g. bottom
region 502) can be interpreted as a gesture if the contacts have a
certain predetermined spacing (e.g., the contacts have centroids
with an x-direction separation of between 1-3 cm). In this manner,
for example, two fingers starting a scroll in the bottom region 502
(and then moving upwards as indicated at 530) will immediately
start the gesture instead of being ignored as edge straddles.
[0046] FIG. 5d illustrates, however, that in certain regions, two
contacts occurring in an edge band can be ignored. In the example
of FIG. 5d, two contacts 532 in side region 526 occurring as a
result of an edge-straddling palm can be ignored to avoid
initiating an inadvertent scroll.
[0047] FIG. 6 illustrates an exemplary touch sensor panel 600
employing edge rejection with a variable width edge band 602
according to embodiments of the invention. In the example of FIG.
6, the width of edge band 602 can be dependent on a major radius of
contact 606. A large major radius (above a certain threshold) of a
contact whose centroid 610 is located within edge band 602 can
cause the edge band to be larger in order to better ignore a thumb
as opposed to a fingertip. The amount or percentage of the major
radius above the threshold can be used to scale up edge band 602.
Alternatively, the width of edge band 602 may not be dependent on
the major radius, but instead can be based on the identification of
a particular finger type. In some embodiments, the variable width
edge band 602 may have a non-uniform width, and may be wider along
one or more edges of the touch sensor panel and narrower along one
or more different edges of the touch sensor panel. For example, a
bottom region 602a of edge band 602 may have a width that is
greater than that of side regions 602b and 602c and top region
602d.
[0048] FIG. 7a illustrates an exemplary trackpad 700 having an
integrated pick button according to embodiments of the invention.
In the example of FIG. 7a, the trackpad 700 can be mechanically
actuated by pushing on the trackpad to generate a "click" input to
implement a mechanical pick button. Trackpads with integrated pick
buttons are described in FIGS. 10-15 below.
[0049] In the trackpad 700 of FIG. 7a, sufficient pressure anywhere
on the surface of the trackpad can cause the click to be generated,
and thus the click itself is not determinative of the location of
the click. Therefore, according to embodiments of the invention,
touch sensing on the trackpad 700 can be used to determine how a
click should be interpreted. When a mechanical click is detected,
the interpretation of the click and the resulting functionality
initiated can depend on where a touch was detected on the trackpad.
In the example embodiment of FIG. 7a, the trackpad 700 is
partitioned into a primary click region 702 and secondary click
region 704. When a touch is detected on the primary click region
702 along with a mechanical click from the trackpad, a left-click
action can be initiated, for example. Similarly, when a touch is
detected on the secondary click region 704 along with a mechanical
click from the trackpad, a right-click action can be initiated, for
example. The partitioning of the trackpad 700 can be implemented in
firmware.
[0050] The example of FIG. 7a shows equal-sized primary and
secondary click regions 702 and 704. However, in other embodiments,
the size or area of the click regions may be unequal to account for
intended usage patterns and avoid misinterpreted clicks. For
example, because the secondary click region 704 may be less
frequently used than the primary click region 702, the secondary
click region may be made smaller and/or located in a region less
likely to be clicked upon, such as the lower right corner of the
trackpad 700.
[0051] FIG. 7b illustrates an exemplary extension of the embodiment
of FIG. 7a in which more than two click regions can be defined. In
the example of FIG. 7b, in addition to primary and secondary click
regions 702 and 704, a number of function key click regions 706,
708 and 710 can be defined. A click of the trackpad 700 along with
a touch in any of these regions can initiate a corresponding
action. Those skilled in the art will understand that because the
partitions are implemented in firmware, any number of regions, in
any number of configurations, can also be employed. In further
embodiments, these regions can dynamically change in accordance
with a particular usage of the computing device (e.g., in
accordance with the application being executed or the user
interface being displayed).
[0052] Embodiments of the invention described above can be
implemented using touch sensor panels of the types described in
U.S. application Ser. No. 11/650,049 entitled "Double-Sided Touch
Sensitive Panel and Flex Circuit Bonding," filed Jan. 3, 2007.
Sense channels of the types described in U.S. application Ser. No.
11/649,998 entitled "Proximity and Multi-Touch Sensor Detection and
Demodulation," filed Jan. 3, 2007 can be used to detect touch and
hover events. The resulting image of touch can be further processed
to determine the location of the touch events, the identification
of finger contacts, and the identification of gestures as described
in U.S. application Ser. No. 11/428,522 entitled "Identifying
Contacts on a Touch Surface," filed Jul. 3, 2006, U.S. application
Ser. No. 11/756,211 entitled "Multi-touch Input Discrimination,"
filed May 31, 2007 and U.S. application Ser. No. 10/903,964
entitled "Gestures for Touch Sensitive Input Devices," filed Jul.
30, 2004 All of the preceding applications referred to in this
paragraph are incorporated by reference herein in their entirety
for all purposes.
[0053] FIG. 8 illustrates exemplary computing system 800 that can
include one or more of the embodiments of the invention described
above. Computing system 800 can include one or more panel
processors 802 and peripherals 804, and panel subsystem 806.
Peripherals 804 can include, but are not limited to, random access
memory (RAM) or other types of memory or storage, watchdog timers
and the like. Panel subsystem 806 can include, but is not limited
to, one or more sense channels 808, channel scan logic 810 and
driver logic 814. Channel scan logic 810 can access RAM 812,
autonomously read data from the sense channels and provide control
for the sense channels. In addition, channel scan logic 810 can
control driver logic 814 to generate stimulation signals 816 at
various frequencies and phases that can be selectively applied to
drive lines of touch sensor panel 824 at a voltage established by
charge pump 815. In some embodiments, panel subsystem 806, panel
processor 802 and peripherals 804 can be integrated into a single
application specific integrated circuit (ASIC).
[0054] Touch sensor panel 824 can include a capacitive sensing
medium having a plurality of drive lines and a plurality of sense
lines, although other sensing media can also be used. Each
intersection, adjacency or near-adjacency of drive and sense lines
can represent a capacitive sensing node and can be viewed as
picture element (pixel) 826, which can be particularly useful when
touch sensor panel 824 is viewed as capturing an "image" of touch.
(In other words, after panel subsystem 806 has determined whether a
touch event has been detected at each touch sensor in the touch
sensor panel, the pattern of touch sensors in the multi-touch panel
at which a touch event occurred can be viewed as an "image" of
touch (e.g. a pattern of fingers touching the panel).) Each sense
line of touch sensor panel 824 can drive sense channel 808 (also
referred to herein as an event detection and demodulation circuit)
in panel subsystem 806.
[0055] Computing system 800 can also include host processor 828 for
receiving outputs from panel processor 802 and performing actions
based on the outputs that can include, but are not limited to,
moving an object such as a cursor or pointer, scrolling or panning,
adjusting control settings, opening a file or document, viewing a
menu, making a selection, executing instructions, operating a
peripheral device coupled to the host device, answering a telephone
call, placing a telephone call, terminating a telephone call,
changing the volume or audio settings, storing information related
to telephone communications such as addresses, frequently dialed
numbers, received calls, missed calls, logging onto a computer or a
computer network, permitting authorized individuals access to
restricted areas of the computer or computer network, loading a
user profile associated with a user's preferred arrangement of the
computer desktop, permitting access to web content, launching a
particular program, encrypting or decoding a message, and/or the
like. Host processor 828 can also perform additional functions that
may not be related to panel processing, and can be coupled to
program storage 832 and display device 830 such as an LCD display
for providing a UI to a user of the device. Display device 830
together with touch sensor panel 824, when located partially or
entirely under the touch sensor panel, or partially or entirely
integrated with the touch sensor panel, can form touch screen
818.
[0056] Note that one or more of the functions described above can
be performed by firmware stored in memory (e.g. one of the
peripherals 804 in FIG. 8) and executed by panel processor 802, or
stored in program storage 832 and executed by host processor 828.
The firmware can also be stored and/or transported within any
computer-readable medium for use by or in connection with an
instruction execution system, apparatus, or device, such as a
computer-based system, processor-containing system, or other system
that can fetch the instructions from the instruction execution
system, apparatus, or device and execute the instructions. In the
context of this document, a "computer-readable storage medium" can
be any storage medium that can contain or store the program for use
by or in connection with the instruction execution system,
apparatus, or device. The computer readable storage medium can
include, but is not limited to, an electronic, magnetic, optical,
electromagnetic, infrared, or semiconductor system, apparatus or
device, a portable computer diskette (magnetic), a random access
memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), an
erasable programmable read-only memory (EPROM) (magnetic), a
portable optical disc such a CD, CD-R, CD-RW, DVD, DVD-R, or
DVD-RW, or flash memory such as compact flash cards, secured
digital cards, USB memory devices, memory sticks, and the like.
[0057] The firmware can also be propagated within any transport
medium for use by or in connection with an instruction execution
system, apparatus, or device, such as a computer-based system,
processor-containing system, or other system that can fetch the
instructions from the instruction execution system, apparatus, or
device and execute the instructions. In the context of this
document, a "transport medium" can be any medium that can
communicate, propagate or transport the program for use by or in
connection with the instruction execution system, apparatus, or
device. The transport readable medium can include, but is not
limited to, an electronic, magnetic, optical, electromagnetic or
infrared wired or wireless propagation medium.
[0058] FIG. 9a illustrates exemplary mobile telephone 936 that can
include touch sensor panel 924 and computing system 942 for
implementing edge rejection and the edge rejection exceptions
described above according to embodiments of the invention. FIG. 9b
illustrates exemplary digital media player 940 that can include
touch sensor panel 924 and computing system 942 for implementing
edge rejection and the edge rejection exceptions described above
according to embodiments of the invention. FIG. 9c illustrates
exemplary personal computer 944 that can include touch sensor panel
(trackpad) 924 and computing system 942 for implementing edge
rejection and the edge rejection exceptions described above
according to embodiments of the invention. The mobile telephone,
media player, and personal computer of FIGS. 9a, 9b and 9c can
advantageously benefit from the edge rejection and the edge
rejection exceptions described above because implementation of
these features can minimize unintended operations while providing
maximum functionality.
[0059] As discussed above, some embodiments of the invention are
directed to trackpads with integrated pick buttons. One example of
a trackpad with an integrated pick button is described below with
reference to FIGS. 10-15. However, it should be understood that
other trackpads or input devices having integrated pick buttons
also fall within the scope of embodiments of the present
invention.
[0060] FIG. 10 is a simplified diagram of an exemplary touch pad
and display according to embodimentsof the invention. In the
example of FIG. 10, a touch-sensitive track pad 10 can be a small
(often rectangular) area that includes a protective/cosmetic shield
12 and a plurality of electrodes 14 disposed underneath the
protective shield 12. Electrodes 14 may be located on a circuit
board, for example a printed circuit board (PCB). For ease of
discussion, a portion of the protective shield 12 has been removed
to show the electrodes 14. Different electrodes 14 or combinations
thereof can represent different x, y positions. In one
configuration, as a finger 16 (or alternatively a stylus, not
shown) approaches the electrode grid 14, the finger may form a
capacitance with one or more electrodes proximate to the finger or
may change existing capacitances between one or more such
electrodes. The circuit board/sensing electronics (not shown)
measures such capacitance changes and produces an input signal 18
which is sent to a host device 20 (e.g., a computing device) having
a display screen 22. The input signal 18 is used to control the
movement of a cursor 24 on a display screen 22. As shown, the input
pointer moves in a similar x, y direction as the detected x, y
finger motion.
[0061] FIG. 11 is a simplified perspective view of an exemplary
input device according to embodiments of the invention. The input
device 30 is generally configured to send information or data to an
electronic device (not shown) in order to perform an action on a
display screen (e.g., via a graphical user interface (GUI))--for
example, moving an input pointer, making a selection, providing
instructions, etc. The input device may interact with the
electronic device through a wired (e.g., cable/connector) or
wireless connection (e.g., IR, bluetooth, etc.).
[0062] The input device 30 may be a stand alone unit or it may be
integrated into the electronic device. When in a stand alone unit,
the input device typically has its own enclosure. When integrated
with an electronic device, the input device typically uses the
enclosure of the electronic device. In either case, the input
device may be structurally coupled to the enclosure as for example
through screws, snaps, retainers, adhesives and the like. In some
cases, the input device may be removably coupled to the electronic
device as for example through a docking station. The electronic
device to which the input device is coupled may correspond to any
consumer related electronic product. By way of example, the
electronic device may correspond to a computer such as a desktop
computer, laptop computer or PDA, a media player such as a music
player, a communication device such as a mobile phone, another
input device such as a keyboard, and the like.
[0063] As shown in FIG. 11, the input device 30 includes a frame 32
(or support structure) and a track pad 34. The frame 32 provides a
structure for supporting the components of the input device. The
frame 32, in the form of a housing, may also enclose or contain the
components of the input device. The components, which include the
track pad 34, may correspond to electrical, optical and/or
mechanical components for operating the input device 30.
[0064] Track pad 34 provides an intuitive interface configured to
provide one or more control functions for controlling various
applications associated with the electronic device to which it is
attached. By way of example, the touch initiated control function
may be used to move an object or perform an action on the display
screen or to make selections or issue commands associated with
operating the electronic device. In order to implement the touch
initiated control function, the track pad 34 may be arranged to
receive input from a finger (or object) moving across the surface
of the track pad 34 (e.g., linearly, radially, angular, etc.), from
a finger holding a particular position on the track pad 34 and/or
by a finger tapping on a particular position of the track pad 34.
As should be appreciated, the touch pad 34 provides easy one-handed
operation, i.e., lets a user interact with the electronic device
with one or more fingers.
[0065] The track pad 34 may be widely varied. For example, the
touch pad 34 may be a conventional track pad based on the Cartesian
coordinate system, or the track pad 34 may be a touch pad based on
a polar coordinate system. An example of a touch pad based on polar
coordinates may be found in U.S. Pat. No. 7,046,230 to Zadesky et
al., entitled "TOUCH PAD FOR HANDHELD DEVICE", filed Jul. 1, 2002,
which is hereby incorporated by reference herein in its entirety
for all purposes.
[0066] The track pad 34 may be used in a relative or absolute mode.
In absolute mode, the track pad 34 reports the absolute coordinates
of where it is being touched (for example x, y in the case of the
Cartesian coordinate system or (r, .theta.) in the case of the
polar coordinate system). In relative mode, the track pad 34
reports the direction and/or distance of change (for example,
left/right, up/down, and the like). In most cases, the signals
produced by the track pad 34 direct motion on the display screen in
a direction similar to the direction of the finger as it is moved
across the surface of the track pad 34.
[0067] The shape of the track pad 34 may be widely varied. For
example, the track pad 34 may be circular, oval, square,
rectangular, triangular, and the like. In general, the outer
perimeter of the track pad 34 defines the working boundary of the
track pad 34. In the illustrated embodiment, the track pad is
rectangular. Rectangular track pads are common on laptop computers.
Circular track pads allow a user to continuously swirl a finger in
a free manner, i.e., the finger can be rotated through 360 degrees
of rotation without stopping. Furthermore, the user can rotate his
or her finger tangentially from all sides thus giving it more range
of finger positions. Both of these features may help when
performing a scrolling function, making circular track pads
advantageous for use with portable media players (e.g., iPod media
players produced by Apple Inc. of Cupertino, Calif.). Furthermore,
the size of the track pad 34 generally corresponds to a size that
allows them to be easily manipulated by a user (e.g., the size of a
finger tip or larger).
[0068] The track pad 34, which generally takes the form of a rigid
planar platform, includes a touchable outer track surface 36 for
receiving a finger (or object) for manipulation of the track pad.
Although not shown in FIG. 11, beneath the touchable outer track
surface 36 is a sensor arrangement that is sensitive to such things
as the pressure and/or motion of a finger thereon. The sensor
arrangement typically includes a plurality of sensors that are
configured to activate as the finger sits on, taps on or passes
over them. In the simplest case, an electrical signal is produced
each time the finger is positioned over a sensor. The number of
signals in a given time frame may indicate location, direction,
speed, and acceleration of the finger on the track pad 34, i.e.,
the more signals, the more the user moved his finger. In most
cases, the signals are monitored by an electronic interface that
converts the number, combination and frequency of the signals into
location, direction, speed and acceleration information. This
information may then be used by the electronic device to perform
the desired control function on the display screen. The sensor
arrangement may be widely varied. By way of example, the sensors
may be based on resistive sensing, surface acoustic wave sensing,
pressure sensing (e.g., strain gauge), infra red sensing, optical
sensing, dispersive signal technology, acoustic pulse recognition,
capacitive sensing and the like.
[0069] In the illustrated embodiment, the track pad 34 is based on
capacitive sensing. As is generally well known, a capacitance-based
track pad is arranged to detect changes in capacitance as the user
moves an object such as a finger around the track pad. In most
cases, the capacitive track pad includes a protective shield, one
or more electrode layers, a circuit board and associated
electronics including an application specific integrated circuit
(ASIC). The protective shield is placed over the electrodes; the
electrodes are mounted on the top surface of the circuit board; and
the ASIC is mounted on the bottom surface of the circuit board. The
protective shield serves to protect the underlayers and to provide
a surface for allowing a finger to slide thereon. The surface is
generally smooth so that the finger does not stick to it when
moved. The protective shield also provides an insulating layer
between the finger and the electrode layers. The electrode layer
includes a plurality of spatially distinct electrodes. Any suitable
number of electrodes may be used. In most cases, it would be
desirable to increase the number of electrodes so as to provide
higher resolution, i.e., more information can be used for things
such as acceleration.
[0070] Capacitive sensing works according to the principals of
capacitance. As should be appreciated, whenever two electrically
conductive members come close to one another without actually
touching, their electric fields interact to form capacitance. In
the configuration discussed above, the first electrically
conductive member is one or more of the electrodes and the second
electrically conductive member is, for example, the finger of the
user. Accordingly, as the finger approaches the touch pad, a tiny
capacitance forms between the finger and the electrodes in close
proximity to the finger. The capacitance in each of the electrodes
is measured by an ASIC located on the backside of the circuit
board. By detecting changes in capacitance at each of the
electrodes, the ASIC can determine the location, direction, speed
and acceleration of the finger as it is moved across the touch pad.
The ASIC can also report this information in a form that can be
used by the electronic device.
[0071] In accordance with one embodiment, track pad 34 is movable
relative to frame 32 so as to initiate another set of signals
(other than just tracking signals). By way of example, track pad 34
in the form of the rigid planar platform may rotate, pivot, slide,
translate, flex and/or the like relative to frame 32. Track pad 34
may be coupled to frame 32 and/or it may be movably restrained by
frame 32. By way of example, track pad 34 may be coupled to frame
32 through screws, axels, pin joints, slider joints, ball and
socket joints, flexure joints, magnets, cushions and/or the like.
Track pad 34 may also float within a space of the frame (e.g.,
gimbal). It should be noted that the input device 30 may
additionally include a combination of joints such as a
pivot/translating joint, pivot/flexure joint, pivot/ball and socket
joint, translating/flexure joint, and the like to increase the
range of motion (e.g., increase the degree of freedom). When moved,
touch pad 34 is configured to actuate a circuit that generates one
or more signals. The circuit generally includes one or more
movement indicators such as switches, sensors, encoders, and the
like. An example of a gimbaled track pad may be found in patent
application Ser. No. 10/643,256, entitled, "MOVABLE TOUCH PAD WITH
ADDED FUNCTIONALITY," filed Aug. 18, 2003, which is hereby
incorporated by reference herein in its entirety for all
purposes.
[0072] In the illustrated embodiment, track pad 34 takes the form
of a depressible button that performs a "picking" action. That is,
a portion of the entire track pad 34 acts like a single or multiple
button such that one or more additional button functions may be
implemented by pressing on track pad 34 rather than tapping on the
track pad or using a separate button/separate zone. As shown in
FIGS. 12A and 12B, according to one embodiment of the invention,
track pad 34 is capable of moving between an upright (or neutral)
position (FIG. 12A) and a depressed (or activate) position (FIG.
12B) when a force from a finger 38, palm, hand, or other object is
applied to the track pad 34. The force should not be so small as to
allow for accidental activation of the button signal, but not so
large as to cause user discomfort by requiring undue pressure.
Track pad 34 is typically biased in the upright position as for
example through a flexure hinge, a spring member, or magnets. Track
pad 34 moves to the activate position when the bias is overcome by
an object pressing on track pad 34. As shown in FIG. 12C, the track
pad 34 may be pivoted at one end such that the activate position is
slightly inclined with respect to the neutral position. When the
finger (or other object) is removed from track pad 34, the biasing
member urges it back towards the neutral position. A shim or other
structure (not shown) may prevent track pad 34 from overshooting
the neutral position as it returns. For example, a portion of frame
32 may extend outwardly above a portion of track pad 34 so as to
stop track pad 34 at the neutral position. In this way, the track
pad surface can be kept flush with frame 32 if desired. For
example, in laptop computers or handheld media devices, it may be
desirable to have the track pad flush with the housing of the
computer or device.
[0073] As shown in FIG. 12A, in the upright/neutral position, track
pad 34 generates tracking signals when an object such as a user's
finger is moved over the top surface of the touch pad in the x,y
plane. Although FIG. 12A depicts the neutral position as being
upright, the neutral position may be situated at any orientation.
As shown in FIG. 12B, in the depressed position (z direction),
track pad 34 generates one or more button signals. The button
signals may be used for various functionalities including but not
limited to making selections or issuing commands associated with
operating an electronic device. By way of example, in the case of a
music player, the button functions may be associated with opening a
menu, playing a song, fast forwarding a song, seeking through a
menu and the like. In the case of a laptop computer, the button
functions can be associated with opening a menu, selecting text,
selecting an icon, and the like. As shown in FIG. 12D, input device
30 may be arranged to provide both the tracking signals and the
button signal at the same time, i.e., simultaneously depressing the
touch pad 34 in the z direction while moving tangentially along the
track surface (i.e., in the x, y directions). In other cases, input
device 30 may be arranged to only provide a button signal when
touch pad 34 is depressed and a tracking signal when the touch pad
34 is upright.
[0074] To elaborate, track pad 34 is configured to actuate one or
more movement indicators, which are capable of generating the
button signal when track pad 34 is moved to the activate position.
The movement indicators are typically located within frame 32 and
may be coupled to track pad 34 and/or frame 32. The movement
indicators may be any combination of switches and sensors. Switches
are generally configured to provide pulsed or binary data such as
activate (on) or deactivate (off). By way of example, an underside
portion of track pad 34 may be configured to contact or engage (and
thus activate) a switch when the user presses on track pad 34. The
sensors, on the other hand, are generally configured to provide
continuous or analog data. By way of example, the sensor may be
configured to measure the position or the amount of tilt of touch
pad 34 relative to the frame when a user presses on the track pad
34. Any suitable mechanical, electrical and/or optical switch or
sensor may be used. For example, tact switches, force sensitive
resistors, pressure sensors, proximity sensors and the like may be
used.
[0075] Track pads 10 and 30 shown in FIGS. 10-12 may, in some
embodiments, be multi-touch trackpads. Multi-touch consists of a
touch surface (screen, table, wall, etc.) or touchpad, as well as
software that recognizes multiple simultaneous touch points, as
opposed to the standard touchscreen (e.g., computer touchpad, ATM),
which recognizes only one touch point. This effect is achieved
through a variety of means, including but not limited to capacitive
sensing, resistive sensing, surface acoustic wave sensing, heat,
finger pressure, high capture rate cameras, infrared light, optic
capture, tuned electromagnetic induction, and shadow capture. An
example of a multi-touch mobile phone is the iPhone produced by
Apple Inc. of Cupertino, Calif. An example of a multi-touch media
device is the iPod Touch produced by Apple Inc. Examples of laptop
computers having multi-touch track pads are the MacBook Air and
MacBook Pro produced by Apple Inc. All of the input devices
described herein may employ multi-touch technology in some
embodiments; alternatively the input devices described herein may
employ single touch track pads.
[0076] FIG. 13 is a simplified block diagram of a computing system
39, in accordance with one embodiment of the present invention. The
computing system generally includes an input device 40 operatively
connected to a computing device 42. By way of example, the input
device 40 may generally correspond to the input device 30 shown in
FIGS. 11 and 12, and the computing device 42 may correspond to a
laptop computer, desktop computer, PDA, media player, mobile phone,
smart phone, video game or the like. As shown, input device 40
includes a depressible track pad 44 and one or more movement
indicators 46. Track pad 44 is configured to generate tracking
signals and movement indicator 46 is configured to generate a
button signal when the track pad 44 is depressed. Although track
pad 44 may be widely varied, in this embodiment, track pad 44
includes capacitance sensors 48 and a control system 50 for
acquiring the position signals from sensors 48 and supplying the
signals to computing device 42. Control system 50 may include an
application specific integrated circuit (ASIC) that is configured
to monitor the signals from sensors 48, to compute the location
(Cartesian or angular), direction, speed and acceleration of the
monitored signals and to report this information to a processor of
computing device 42. Movement indicator 46 may also be widely
varied. In this embodiment, however, movement indicator 46 takes
the form of a switch that generates a button signal when track pad
44 is depressed. Switch 46 may correspond to a mechanical,
electrical or optical style switch. In one particular
implementation, switch 46 is a mechanical style switch that
includes a protruding actuator 52 that may be pushed by track pad
44 to generate the button signal. By way of example, the switch may
be a tact switch or tactile dome.
[0077] Both track pad 44 and switch 46 are operatively coupled to
computing device 42 through a communication interface 54. The
communication interface provides a connection point for direct or
indirect connection between the input device and the electronic
device. Communication interface 54 may be wired (wires, cables,
connectors) or wireless (e.g., transmitter/receiver).
[0078] Computing device 42 generally includes a processor 55 (e.g.,
CPU or microprocessor) configured to execute instructions and to
carry out operations associated with the computing device 42. For
example, using instructions retrieved for example from memory, the
processor may control the reception and manipulation of input and
output data between components of the computing device 42. In most
cases, processor 55 executes instruction under the control of an
operating system or other software. Processor 55 can be a
single-chip processor or can be implemented with multiple
components.
[0079] Computing device 42 also includes an input/output (I/O)
controller 56 that is operatively coupled to processor 54. I/O
controller 56 may be integrated with processor 54 or it may be a
separate component, as shown. I/O controller 56 is generally
configured to control interactions with one or more I/O devices
that can be coupled to computing device 42, for example, input
device 40. I/O controller 56 generally operates by exchanging data
between computing device 42 and I/O devices that desire to
communicate with computing device 42.
[0080] Computing device 42 also includes a display controller 58
that is operatively coupled to processor 54. Display controller 58
may be integrated with processor 54 or it may be a separate
component, as shown. Display controller 58 is configured to process
display commands to produce text and graphics on a display screen
60. By way of example, display screen 60 may be a monochrome
display, color graphics adapter (CGA) display, enhanced graphics
adapter (EGA) display, variable-graphics-array (VGA) display, super
VGA display, liquid crystal display (LCD) (e.g., active matrix,
passive matrix and the like), cathode ray tube (CRT), plasma
displays, backlit light-emitting diode (LED) LCD displays, or the
like.
[0081] In one embodiment (not shown), track pad 44 can comprise a
glass surface functioning not only as a touch-sensitive surface,
but also as a display screen; in this case display screen 60 shown
in FIG. 13 would be integrated with the glass surface of the track
pad 44. This could be useful in computing devices (e.g., media
players or mobile phones) having touch sensitive displays. An
example of a media player having a touch sensitive display is the
iPod Touch produced by Apple Inc. of Cupertino Calif. An example of
a mobile phone having a touch sensitive display is the iPhone
produced by Apple Inc. of Cupertino Calif.
[0082] In most cases, processor 54 together with an operating
system operates to execute computer code and produce and use data.
The computer code and data may reside within a program storage area
62 that is operatively coupled to processor 54. Program storage
area 62 generally provides a place to hold data that is being used
by computing device 42. By way of example, the program storage area
may include Read-Only Memory (ROM), Random-Access Memory (RAM),
hard disk drive and/or the like. The computer code and data could
also reside on a removable program medium and loaded or installed
onto the computing device when needed. In one embodiment, program
storage area 62 is configured to store information for controlling
how the tracking and button signals generated by input device 40
are used by computing device 42.
[0083] FIG. 14 shows one embodiment of an input device, generally
shown at 70, comprising a track pad 72 connected to a frame 76.
Frame 76 may be a housing for a stand alone input device, or it may
be a casing for another device which incorporates track pad 72, for
example a laptop computer, desktop computer, hand held media
device, PDA, mobile phone, smart phone, etc. Track pad 72 includes
various layers including an outer touch-sensitive track surface 74
for tracking finger movements. Track surface 74 may also provide a
low friction cosmetic surface. In one embodiment, track pad 72 is
based on capacitive sensing; therefore, it includes an electrode
layer 80, which, for example, may be implemented on a PCB. In the
case of capacitive sensing, track surface 74 is a dielectric
material. A stiffener 84 is located below electrode layer 80.
Stiffener 84 is shown in FIG. 14 and FIG. 15, but in some
embodiments may be omitted. Stiffener 84 may be used to compensate
for the inherent flexibility of electrode layer 80. Electrode layer
80 responds to finger movements along to track surface 74 by
sending signals to sensor 82. In the case of capacitive sensing,
electrode layer 80 registers changes in capacitance based on finger
movements and sensor 82 is a capacitive sensor. In this way, track
pad 72 incorporates a touch sensor arrangement. Sensor 82 is shown
disposed on the bottom of electrode layer 80, but it may be located
elsewhere in other embodiments. If, as in the illustrated
embodiment, sensor 82 is located on a movable part of track pad 72,
the input device may incorporate a flexible electrical connection
(not shown) capable of moving with the system.
[0084] A movement indicator 78 is disposed on the bottom of track
pad 72. Movement indicator 78 may be widely varied, however, in
this embodiment it takes the form of a mechanical switch, which is
typically disposed between the track pad 72 and the frame 76. In
other embodiments, movement indicator 78 may be a sensor, for
example an electrical sensor. Movement indicator 78 may be attached
to frame 76 or to track pad 72. In the illustrated embodiment,
movement indicator 78 is attached to the bottom side of electrode
layer 80. By way of example, if electrode layer 80 is located on a
PCB, movement indicator 78 may be located on the bottom of the PCB.
In another example, movement indicator 78 may tack the form of a
tact switches and more particularly, may be an SMT dome switches
(dome switch packaged for SMT).
[0085] Track pad 72 is shown in its neutral position in FIG. 14,
where movement sensor 78 is not in contact with frame 76. When a
user applies a downward pressure to track surface 74, track pad 72
may move downward causing movement sensor 78 to register this
change in position. In the illustrated embodiment, movement sensor
78 (a tact switch) would contact either frame 76, or in this case
set screw 88. Set screw 88 may be manually adjusted to alter the
distance between the neutral and activate positions. In one
embodiment (not shown), set screw 88 may directly abut movement
sensor 78 in the neutral position, such that there is no slack or
pre-travel in the system. A flexure hinge 86 connects track pad 72
with frame 76. Flexure hinge 86 is a resilient material that flexes
when a force is applied, but exerts a restoring force so as to urge
track pad 72 back towards the neutral position. In one embodiment,
flexure hinge 86 may be thin spring steel.
[0086] As shown in FIG. 15, flexure hinge 86 will flex when a user
pushes down on track surface 74. Flexure 86 also urges track pad 72
towards its neutral position, which in the illustrated embodiment
shown in FIG. 14 is horizontal. In this way, a user can press down
virtually anywhere on track surface 74 and cause a "pick," meaning
that movement indicator 78 will register this depression. This is
in contrast to prior track pads which incorporate separate track
zones and pick zones. Being able to pick anywhere on track surface
74 will provide the user with a more intuitive and pleasurable
interface. For example, a user may be able to generate tracking and
button signals with a single finger without ever having to remove
the finger from track surface 74. In contrast, a user operating a
track pad with separate track and pick zones may, for example, use
a right hand for tracking and a left hand for picking, or a
forefinger for tracking and thumb picking.
[0087] A shoulder 90, which may be an extension of frame 76 or a
discrete member, blocks track pad 72 from travelling past its
neutral position by contacting a part of track pad 72, for example
stiffener 84. In this way, track surface 74 may be kept
substantially flush with a top surface of frame 76. There may be a
shock absorber or upstop (not shown) incorporated in conjunction
with shoulder 90 to cushion contacts between track pad 72 and
shoulder 90.
[0088] As should be appreciated, the pick generated by pressing on
track surface 74 may include selecting an item on the screen,
opening a file or document, executing instructions, starting a
program, viewing a menu, and/or the like. The button functions may
also include functions that make it easier to navigate through the
electronic system, as for example, zoom, scroll, open different
menus, home the input pointer, perform keyboard related actions
such as enter, delete, insert, page up/down, and the like.
[0089] Flexure hinge 86 allows for a movable track pad in the
minimum vertical space possible. Minimum vertical space is achieved
because flexure hinge 86 is thin and is generally situated parallel
to a bottom layer of track pad 72; consequently, flexure hinge 86
does not appreciably add to the thickness of track pad 72.
Therefore, this arrangement is feasible for use in ultrathin laptop
computers. In such ultrathin laptop computer applications, vertical
space is extremely limited. In the past, the size of electrical
components was often the limiting feature as to how small
electrical devices could be made. Today, electrical components are
increasingly miniaturized, meaning that mechanical components
(e.g., movable track pads) may now be the critical size-limiting
components. With this understanding, it is easy to appreciate why
linear-actuation (e.g., supporting a movable track pad by coil
springs or the like) is not ideal in some applications.
Furthermore, using springs may add unnecessary complexity
(increased part count, higher cost, higher failure rates, etc . . .
) to the manufacturing process. Another disadvantage of springs is
that in some embodiments springs may mask or compromise the tactile
switch force profile. In contrast, flexure 86 can deliver a
substantially consistent feel across the track surface 74, and give
the user a more faithful representation of the tactile switch force
profile.
[0090] Referring now to FIG. 15, according to one embodiment of the
present invention, when a user presses on track surface 74 of track
pad 72, track pad 72 pivots downwardly activates switch 78 disposed
underneath. When activated, switch 78 generates button signals that
may be used by an electronic device connected to input device 70.
Flexure 86 can constrain track pad 72 to move substantially about
only one axis. This can be accomplished by, for example, using
multiple flexures arranged along an axis on one side of track pad
72, such as the rear side. Furthermore, if track pad 72 is made
stiff (for example, by inclusion of stiffener 84 if necessary), a
leveling architecture is achieved. In other words, flexure hinge 86
urges track pad 72 towards its neutral position and also permits
movement about substantially only one axis, i.e., the axis along
which flexure hinge 86 is connected to frame 76.
[0091] Although embodiments of this invention have been fully
described with reference to the accompanying drawings, it is to be
noted that various changes and modifications will become apparent
to those skilled in the art. Such changes and modifications are to
be understood as being included within the scope of embodiments of
this invention as defined by the appended claims.
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