U.S. patent application number 13/645101 was filed with the patent office on 2013-05-02 for determining hover distance of an active stylus.
The applicant listed for this patent is Kishore Sundara-Rajan, Esat Yilmaz. Invention is credited to Kishore Sundara-Rajan, Esat Yilmaz.
Application Number | 20130106777 13/645101 |
Document ID | / |
Family ID | 48171896 |
Filed Date | 2013-05-02 |
United States Patent
Application |
20130106777 |
Kind Code |
A1 |
Yilmaz; Esat ; et
al. |
May 2, 2013 |
Determining Hover Distance of an Active Stylus
Abstract
In one embodiment, a change in capacitance at one or more
capacitive nodes of a touch sensor of a device is detected. The
change in capacitance is detected in response to a stylus being in
proximity with but not touching the touch sensor. The stylus
includes one or more computer-readable media embodying logic and
one or more electrodes for effecting charge transfer wirelessly in
the device through the touch sensor of the device. The change in
capacitance is analyzed to determine a distance between the stylus
and the device.
Inventors: |
Yilmaz; Esat; (Santa Cruz,
CA) ; Sundara-Rajan; Kishore; (San Jose, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Yilmaz; Esat
Sundara-Rajan; Kishore |
Santa Cruz
San Jose |
CA
CA |
US
US |
|
|
Family ID: |
48171896 |
Appl. No.: |
13/645101 |
Filed: |
October 4, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61553114 |
Oct 28, 2011 |
|
|
|
Current U.S.
Class: |
345/174 ;
178/18.06 |
Current CPC
Class: |
G06F 3/0445 20190501;
G06F 3/0441 20190501; G06F 21/32 20130101; G06F 3/0446 20190501;
G06F 3/0442 20190501; G06F 3/03545 20130101; G06F 3/0443
20190501 |
Class at
Publication: |
345/174 ;
178/18.06 |
International
Class: |
G06F 3/044 20060101
G06F003/044 |
Claims
1. A method comprising: detecting a change in capacitance at one or
more capacitive nodes of a touch sensor of a device in response to
a stylus being in proximity with but not touching the touch sensor,
the stylus comprising one or more computer-readable media embodying
logic and one or more electrodes for effecting charge transfer
wirelessly in the device through the touch sensor of the device;
and analyzing the change in capacitance to determine a distance
between the stylus and the device.
2. The method of claim 1, wherein the electrodes are located in a
tip of the stylus.
3. The method of claim 1, wherein the device detects the change in
capacitance at the one or more capacitive nodes of the touch sensor
and analyzes the change in capacitance to determine the distance
between the stylus and the device.
4. The method of claim 2, wherein the stylus detects the change in
capacitance at the stylus electrodes and analyzes the change in
capacitance to determine the distance between the stylus and the
device.
5. The method of claim 1, wherein analyzing the change in
capacitance comprises analyzing a magnitude of the change in
capacitance.
6. The method of claim 1, wherein analyzing the change in
capacitance comprises analyzing the change in capacitance in each
of the one or more capacitive nodes of the touch sensor.
7. The method of claim 1, wherein the distance between the stylus
and the device is measured between one or more of the electrodes of
the stylus and the touch sensor.
8. One or more computer-readable non-transitory storage media
embodying logic that is operable when executed to: detect a change
in capacitance at one or more capacitive nodes of a touch sensor of
a device in response to a stylus being in proximity with but not
touching the touch sensor, the stylus comprising one or more
electrodes for effecting charge transfer wirelessly in the device
through the touch sensor of the device; and analyze the change in
capacitance to determine a distance between the stylus and the
device.
9. The media of claim 8, wherein the electrodes are located in a
tip of the stylus.
10. The media of claim 8, wherein the logic is located at the
device.
11. The media of claim 9, wherein the stylus further comprises one
or more computer-readable non-transitory storage media embodying
logic that is operable when executed to detect a change in
capacitance at the stylus electrodes and analyze the change in
capacitance to determine the distance between the stylus and the
device.
12. The media of claim 8, wherein analyzing the change in
capacitance comprises analyzing a magnitude of the change in
capacitance.
13. The media of claim 8, wherein analyzing the change in
capacitance comprises analyzing the change in capacitance in each
of the one or more capacitive nodes of the touch sensor.
14. The media of claim 8, wherein the distance between the stylus
and the device is measured between one or more of the electrodes of
the stylus and the touch sensor.
15. A device comprising: a touch sensor comprising one or more
capacitive nodes; and one or more computer-readable non-transitory
storage media embodying logic that is operable when executed to:
detect a change in capacitance at a capacitive node in response to
a stylus being in proximity with but not touching the touch sensor,
the stylus comprising one or more electrodes for effecting charge
transfer wirelessly in the device through the touch sensor of the
device; and analyze the change in capacitance to determine a
distance between the stylus and the device.
16. The device of claim 15, wherein the electrodes are located in a
tip of the stylus.
17. The device of claim 16, wherein the stylus further comprises
one or more computer-readable non-transitory storage media
embodying logic that is operable when executed to detect a change
in capacitance at the stylus electrodes and analyze the change in
capacitance to determine the distance between the stylus and the
device.
18. The device of claim 15, wherein analyzing the change in
capacitance comprises analyzing a magnitude of the change in
capacitance.
19. The device of claim 15, wherein analyzing the change in
capacitance comprises analyzing the change in capacitance in each
of the one or more capacitive nodes of the touch sensor.
20. The device of claim 15, wherein the distance between the stylus
and the device is measured between one or more of the electrodes of
the stylus and the touch sensor.
Description
RELATED APPLICATION
[0001] This application claims the benefit, under 35 U.S.C.
.sctn.119(e), of U.S. Provisional Patent Application No.
61/553,114, filed 28 Oct. 2011, which is incorporated herein by
reference.
TECHNICAL FIELD
[0002] This disclosure generally relates to active styluses.
BACKGROUND
[0003] A touch sensor may detect the presence and location of a
touch or the proximity of an object (such as a user's finger or a
stylus) within a touch-sensitive area of the touch sensor overlaid
on a display screen, for example. In a touch-sensitive-display
application, the touch sensor may enable a user to interact
directly with what is displayed on the screen, rather than
indirectly with a mouse or touch pad. A touch sensor may be
attached to or provided as part of a desktop computer, laptop
computer, tablet computer, personal digital assistant (PDA),
smartphone, satellite navigation device, portable media player,
portable game console, kiosk computer, point-of-sale device, or
other suitable device. A control panel on a household or other
appliance may include a touch sensor.
[0004] There are a number of different types of touch sensors, such
as, for example, resistive touch screens, surface acoustic wave
touch screens, and capacitive touch screens. Herein, reference to a
touch sensor may encompass a touch screen, and vice versa, where
appropriate. When an object touches or comes within proximity of
the surface of the capacitive touch screen, a change in capacitance
may occur within the touch screen at the location of the touch or
proximity. A touch-sensor controller may process the change in
capacitance to determine its position on the touch screen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 illustrates an example touch sensor with an example
touch-sensor controller.
[0006] FIG. 2 illustrates an example active stylus exterior.
[0007] FIG. 3 illustrates an example active stylus interior.
[0008] FIG. 4 illustrates an example active stylus with touch
sensor device.
[0009] FIGS. 5A and 5B illustrate one or more electrodes in a tip
of an active stylus, the electrodes transmitting voltage signals
that communicate the stylus's relative location or movement to a
touch-sensitive device.
[0010] FIG. 6 illustrates a method for determining the hover
distance of an active stylus.
DESCRIPTION OF EXAMPLE EMBODIMENTS
[0011] FIG. 1 illustrates an example touch sensor 10 with an
example touch-sensor controller 12. Touch sensor 10 and
touch-sensor controller 12 may detect the presence and location of
a touch or the proximity of an object within a touch-sensitive area
of touch sensor 10. Herein, reference to a touch sensor may
encompass both the touch sensor and its touch-sensor controller,
where appropriate. Similarly, reference to a touch-sensor
controller may encompass both the touch-sensor controller and its
touch sensor, where appropriate. Touch sensor 10 may include one or
more touch-sensitive areas, where appropriate. Touch sensor 10 may
include an array of drive and sense electrodes (or an array of
electrodes of a single type) disposed on one or more substrates,
which may be made of a dielectric material. Herein, reference to a
touch sensor may encompass both the electrodes of the touch sensor
and the substrate(s) that they are disposed on, where appropriate.
Alternatively, where appropriate, reference to a touch sensor may
encompass the electrodes of the touch sensor, but not the
substrate(s) that they are disposed on.
[0012] An electrode (whether a ground electrode, guard electrode,
drive electrode, or sense electrode) may be an area of conductive
material forming a shape, such as for example a disc, square,
rectangle, thin line, other suitable shape, or suitable combination
of these. One or more cuts in one or more layers of conductive
material may (at least in part) create the shape of an electrode,
and the area of the shape may (at least in part) be bounded by
those cuts. In particular embodiments, the conductive material of
an electrode may occupy approximately 100% of the area of its
shape. As an example and not by way of limitation, an electrode may
be made of indium tin oxide (ITO) and the ITO of the electrode may
occupy approximately 100% of the area of its shape (sometimes
referred to as a 100% fill), where appropriate. In particular
embodiments, the conductive material of an electrode may occupy
substantially less than 100% of the area of its shape. As an
example and not by way of limitation, an electrode may be made of
fine lines of metal or other conductive material (FLM), such as for
example copper, silver, or a copper- or silver-based material, and
the fine lines of conductive material may occupy approximately 5%
of the area of its shape in a hatched, mesh, or other suitable
pattern. Herein, reference to FLM encompasses such material, where
appropriate. Although this disclosure describes or illustrates
particular electrodes made of particular conductive material
forming particular shapes with particular fill percentages having
particular patterns, this disclosure contemplates any suitable
electrodes made of any suitable conductive material forming any
suitable shapes with any suitable fill percentages having any
suitable patterns.
[0013] Where appropriate, the shapes of the electrodes (or other
elements) of a touch sensor may constitute in whole or in part one
or more macro-features of the touch sensor. One or more
characteristics of the implementation of those shapes (such as, for
example, the conductive materials, fills, or patterns within the
shapes) may constitute in whole or in part one or more
micro-features of the touch sensor. One or more macro-features of a
touch sensor may determine one or more characteristics of its
functionality, and one or more micro-features of the touch sensor
may determine one or more optical features of the touch sensor,
such as transmittance, refraction, or reflection.
[0014] A mechanical stack may contain the substrate (or multiple
substrates) and the conductive material forming the drive or sense
electrodes of touch sensor 10. As an example and not by way of
limitation, the mechanical stack may include a first layer of
optically clear adhesive (OCA) beneath a cover panel. The cover
panel may be clear and made of a resilient material suitable for
repeated touching, such as for example glass, polycarbonate, or
poly(methyl methacrylate) (PMMA). This disclosure contemplates any
suitable cover panel made of any suitable material. The first layer
of OCA may be disposed between the cover panel and the substrate
with the conductive material forming the drive or sense electrodes.
The mechanical stack may also include a second layer of OCA and a
dielectric layer (which may be made of polyethylene terephthalate
(PET) or another suitable material, similar to the substrate with
the conductive material forming the drive or sense electrodes). As
an alternative, where appropriate, a thin coating of a dielectric
material may be applied instead of the second layer of OCA and the
dielectric layer. The second layer of OCA may be disposed between
the substrate with the conductive material making up the drive or
sense electrodes and the dielectric layer, and the dielectric layer
may be disposed between the second layer of OCA and an air gap to a
display of a device including touch sensor 10 and touch-sensor
controller 12. As an example only and not by way of limitation, the
cover panel may have a thickness of approximately 1 mm; the first
layer of OCA may have a thickness of approximately 0.05 mm; the
substrate with the conductive material forming the drive or sense
electrodes may have a thickness of approximately 0.05 mm; the
second layer of OCA may have a thickness of approximately 0.05 mm;
and the dielectric layer may have a thickness of approximately 0.05
mm. Although this disclosure describes a particular mechanical
stack with a particular number of particular layers made of
particular materials and having particular thicknesses, this
disclosure contemplates any suitable mechanical stack with any
suitable number of any suitable layers made of any suitable
materials and having any suitable thicknesses. As an example and
not by way of limitation, in particular embodiments, a layer of
adhesive or dielectric may replace the dielectric layer, second
layer of OCA, and air gap described above, with there being no air
gap to the display.
[0015] One or more portions of the substrate of touch sensor 10 may
be made of polyethylene terephthalate (PET) or another suitable
material. This disclosure contemplates any suitable substrate with
any suitable portions made of any suitable material. In particular
embodiments, the drive or sense electrodes in touch sensor 10 may
be made of ITO in whole or in part. In particular embodiments, the
drive or sense electrodes in touch sensor 10 may be made of fine
lines of metal or other conductive material. As an example and not
by way of limitation, one or more portions of the conductive
material may be copper or copper-based and have a thickness of
approximately 5 .mu.m or less and a width of approximately 10 .mu.m
or less. As another example, one or more portions of the conductive
material may be silver or silver-based and similarly have a
thickness of approximately 5 .mu.m or less and a width of
approximately 10 .mu.m or less. This disclosure contemplates any
suitable electrodes made of any suitable material.
[0016] Touch sensor 10 may implement a capacitive form of touch
sensing. In a mutual-capacitance implementation, touch sensor 10
may include an array of drive and sense electrodes forming an array
of capacitive nodes. A drive electrode and a sense electrode may
form a capacitive node. The drive and sense electrodes forming the
capacitive node may come near each other, but not make electrical
contact with each other. Instead, the drive and sense electrodes
may be capacitively coupled to each other across a space between
them. A pulsed or alternating voltage applied to the drive
electrode (by touch-sensor controller 12) may induce a charge on
the sense electrode, and the amount of charge induced may be
susceptible to external influence (such as a touch or the proximity
of an object). When an object touches or comes within proximity of
the capacitive node, a change in capacitance may occur at the
capacitive node and touch-sensor controller 12 may measure the
change in capacitance. By measuring changes in capacitance
throughout the array, touch-sensor controller 12 may determine the
position of the touch or proximity within the touch-sensitive
area(s) of touch sensor 10.
[0017] In a self-capacitance implementation, touch sensor 10 may
include an array of electrodes of a single type that may each form
a capacitive node. When an object touches or comes within proximity
of the capacitive node, a change in self-capacitance may occur at
the capacitive node and controller 12 may measure the change in
capacitance, for example, as a change in the amount of charge
needed to raise the voltage at the capacitive node by a
pre-determined amount. As with a mutual-capacitance implementation,
by measuring changes in capacitance throughout the array,
controller 12 may determine the position of the touch or proximity
within the touch-sensitive area(s) of touch sensor 10. This
disclosure contemplates any suitable form of capacitive touch
sensing, where appropriate.
[0018] In particular embodiments, one or more drive electrodes may
together form a drive line running horizontally or vertically or in
any suitable orientation. Similarly, one or more sense electrodes
may together form a sense line running horizontally or vertically
or in any suitable orientation. In particular embodiments, drive
lines may run substantially perpendicular to sense lines. Herein,
reference to a drive line may encompass one or more drive
electrodes making up the drive line, and vice versa, where
appropriate. Similarly, reference to a sense line may encompass one
or more sense electrodes making up the sense line, and vice versa,
where appropriate.
[0019] Touch sensor 10 may have drive and sense electrodes disposed
in a pattern on one side of a single substrate. In such a
configuration, a pair of drive and sense electrodes capacitively
coupled to each other across a space between them may form a
capacitive node. For a self-capacitance implementation, electrodes
of only a single type may be disposed in a pattern on a single
substrate. In addition or as an alternative to having drive and
sense electrodes disposed in a pattern on one side of a single
substrate, touch sensor 10 may have drive electrodes disposed in a
pattern on one side of a substrate and sense electrodes disposed in
a pattern on another side of the substrate. Moreover, touch sensor
10 may have drive electrodes disposed in a pattern on one side of
one substrate and sense electrodes disposed in a pattern on one
side of another substrate. In such configurations, an intersection
of a drive electrode and a sense electrode may form a capacitive
node. Such an intersection may be a location where the drive
electrode and the sense electrode "cross" or come nearest each
other in their respective planes. The drive and sense electrodes do
not make electrical contact with each other--instead they are
capacitively coupled to each other across a dielectric at the
intersection. Although this disclosure describes particular
configurations of particular electrodes forming particular nodes,
this disclosure contemplates any suitable configuration of any
suitable electrodes forming any suitable nodes. Moreover, this
disclosure contemplates any suitable electrodes disposed on any
suitable number of any suitable substrates in any suitable
patterns.
[0020] As described above, a change in capacitance at a capacitive
node of touch sensor 10 may indicate a touch or proximity input at
the position of the capacitive node. Touch-sensor controller 12 may
detect and process the change in capacitance to determine the
presence and location of the touch or proximity input. Touch-sensor
controller 12 may then communicate information about the touch or
proximity input to one or more other components (such one or more
central processing units (CPUs)) of a device that includes touch
sensor 10 and touch-sensor controller 12, which may respond to the
touch or proximity input by initiating a function of the device (or
an application running on the device). Although this disclosure
describes a particular touch-sensor controller having particular
functionality with respect to a particular device and a particular
touch sensor, this disclosure contemplates any suitable
touch-sensor controller having any suitable functionality with
respect to any suitable device and any suitable touch sensor.
[0021] Touch-sensor controller 12 may be one or more integrated
circuits (ICs), such as for example general-purpose
microprocessors, microcontrollers, programmable logic devices
(PLDs) or programmable logic arrays (PLAs), fuse-programmable
arrays (FPGAs), or application-specific ICs (ASICs). In particular
embodiments, touch-sensor controller 12 comprises analog circuitry,
digital logic, and digital non-volatile memory. In particular
embodiments, touch-sensor controller 12 is disposed on a flexible
printed circuit (FPC) bonded to the substrate of touch sensor 10,
as described below. The FPC may be active or passive, where
appropriate. In particular embodiments multiple touch-sensor
controllers 12 are disposed on the FPC. Touch-sensor controller 12
may include a processor unit, a drive unit, a sense unit, and a
storage unit. The drive unit may supply drive signals to the drive
electrodes of touch sensor 10. The sense unit may sense charge at
the capacitive nodes of touch sensor 10 and provide measurement
signals to the processor unit representing capacitances at the
capacitive nodes. The processor unit may control the supply and
timing of drive signals to the drive electrodes by the drive unit
and process measurement signals from the sense unit to detect and
process the presence and location of a touch or proximity input
within the touch-sensitive area(s) of touch sensor 10. The
processor unit may also track changes in the position of a touch or
proximity input within the touch-sensitive area(s) of touch sensor
10. The storage unit may store programming for execution by the
processor unit, including programming for controlling the drive
unit to supply drive signals to the drive electrodes, programming
for processing measurement signals from the sense unit, and other
suitable programming, where appropriate. Although this disclosure
describes a particular touch-sensor controller having a particular
implementation with particular components, this disclosure
contemplates any suitable touch-sensor controller having any
suitable implementation with any suitable components.
[0022] Tracks 14 of conductive material disposed on the substrate
of touch sensor 10 may couple the drive or sense electrodes of
touch sensor 10 to connection pads 16, also disposed on the
substrate of touch sensor 10. As described below, connection pads
16 facilitate coupling of tracks 14 to touch-sensor controller 12.
Tracks 14 may extend into or around (e.g. at the edges of) the
touch-sensitive area(s) of touch sensor 10. Particular tracks 14
may provide drive connections for coupling touch-sensor controller
12 to drive electrodes of touch sensor 10, through which the drive
unit of touch-sensor controller 12 may supply drive signals to the
drive electrodes. Other tracks 14 may provide sense connections for
coupling touch-sensor controller 12 to sense electrodes of touch
sensor 10, through which the sense unit of touch-sensor controller
12 may sense charge at the capacitive nodes of touch sensor 10.
Tracks 14 may be made of fine lines of metal or other conductive
material. As an example and not by way of limitation, the
conductive material of tracks 14 may be copper or copper-based and
have a width of approximately 100 .mu.m or less. As another
example, the conductive material of tracks 14 may be silver or
silver-based and have a width of approximately 100 .mu.m or less.
In particular embodiments, tracks 14 may be made of ITO in whole or
in part in addition or as an alternative to fine lines of metal or
other conductive material. Although this disclosure describes
particular tracks made of particular materials with particular
widths, this disclosure contemplates any suitable tracks made of
any suitable materials with any suitable widths. In addition to
tracks 14, touch sensor 10 may include one or more ground lines
terminating at a ground connector (which may be a connection pad
16) at an edge of the substrate of touch sensor 10 (similar to
tracks 14).
[0023] Connection pads 16 may be located along one or more edges of
the substrate, outside the touch-sensitive area(s) of touch sensor
10. As described above, touch-sensor controller 12 may be on an
FPC. Connection pads 16 may be made of the same material as tracks
14 and may be bonded to the FPC using an anisotropic conductive
film (ACF). Connection 18 may include conductive lines on the FPC
coupling touch-sensor controller 12 to connection pads 16, in turn
coupling touch-sensor controller 12 to tracks 14 and to the drive
or sense electrodes of touch sensor 10. In another embodiment,
connection pads 16 may be connected to an electro-mechanical
connector (such as a zero insertion force wire-to-board connector);
in this embodiment, connection 18 may not need to include an FPC.
This disclosure contemplates any suitable connection 18 between
touch-sensor controller 12 and touch sensor 10.
[0024] FIG. 2 illustrates an example exterior of an example active
stylus 20. Active stylus 20 may include one or more components,
such as buttons 30 or sliders 32 and 34 integrated with an outer
body 22. These external components may provide for interaction
between active stylus 20 and a user or between a device and a user.
As an example and not by way of limitation, interactions may
include communication between active stylus 20 and a device,
enabling or altering functionality of active stylus 20 or a device,
or providing feedback to or accepting input from one or more users.
The device may by any suitable device, such as, for example and
without limitation, a desktop computer, laptop computer, tablet
computer, personal digital assistant (PDA), smartphone, satellite
navigation device, portable media player, portable game console,
kiosk computer, point-of-sale device, or other suitable device.
Although this disclosure provides specific examples of particular
components configured to provide particular interactions, this
disclosure contemplates any suitable component configured to
provide any suitable interaction. Active stylus 20 may have any
suitable dimensions with outer body 22 made of any suitable
material or combination of materials, such as, for example and
without limitation, plastic or metal. In particular embodiments,
exterior components (e.g. 30 or 32) of active stylus 20 may
interact with internal components or programming of active stylus
20 or may initiate one or more interactions with one or more
devices or other active styluses 20.
[0025] As described above, actuating one or more particular
components may initiate an interaction between active stylus 20 and
a user or between the device and the user. Components of active
stylus 20 may include one or more buttons 30 or one or more sliders
32 and 34. As an example and not by way of limitation, buttons 30
or sliders 32 and 34 may be mechanical or capacitive and may
function as a roller, trackball, or wheel. As another example, one
or more sliders 32 or 34 may function as a vertical slider 34
aligned along a longitudinal axis, while one or more wheel sliders
32 may be aligned along the circumference of active stylus 20. In
particular embodiments, capacitive sliders 32 and 34 or buttons 30
may be implemented using one or more touch-sensitive areas.
Touch-sensitive areas may have any suitable shape, dimensions,
location, or be made from any suitable material. As an example and
not by way of limitation, sliders 32 and 34 or buttons 30 may be
implemented using areas of flexible mesh formed using lines of
conductive material. As another example, sliders 32 and 34 or
buttons 30 may be implemented using a FPC.
[0026] Active stylus 20 may have one or more components configured
to provide feedback to or accepting feedback from a user, such as,
for example and without limitation, tactile, visual, or audio
feedback. Active stylus 20 may include one or more ridges or
grooves 24 on its outer body 22. Ridges or grooves 24 may have any
suitable dimensions, have any suitable spacing between ridges or
grooves, or be located at any suitable area on outer body 22 of
active stylus 20. As an example and not by way of limitation,
ridges 24 may enhance a user's grip on outer body 22 of active
stylus 20 or provide tactile feedback to or accept tactile input
from a user. Active stylus 20 may include one or more audio
components 38 capable of transmitting and receiving audio signals.
As an example and not by way of limitation, audio component 38 may
contain a microphone capable of recording or transmitting one or
more users' voices. As another example, audio component 38 may
provide an auditory indication of a power status of active stylus
20. Active stylus 20 may include one or more visual feedback
components 36, such as a light-emitting diode (LED) indicator. As
an example and not by way of limitation, visual feedback component
36 may indicate a power status of active stylus 20 to the user.
[0027] One or more modified surface areas 40 may form one or more
components on outer body 22 of active stylus 20. Properties of
modified surface areas 40 may be different than properties of the
remaining surface of outer body 22. As an example and not by way of
limitation, modified surface area 40 may be modified to have a
different texture, temperature, or electromagnetic characteristic
relative to the surface properties of the remainder of outer body
22. Modified surface area 40 may be capable of dynamically altering
its properties, for example by using haptic interfaces or rendering
techniques. A user may interact with modified surface area 40 to
provide any suitable functionally. For example and not by way of
limitation, dragging a finger across modified surface area 40 may
initiate an interaction, such as data transfer, between active
stylus 20 and a device.
[0028] One or more components of active stylus 20 may be configured
to communicate data between active stylus 20 and the device. For
example, active stylus 20 may include one or more tips 26 or nibs.
Tip 26 may include one or more electrodes configured to communicate
data between active stylus 20 and one or more devices or other
active styluses. Tip 26 may be made of any suitable material, such
as a conductive material, and have any suitable dimensions, such
as, for example, a diameter of 1 mm or less at its terminal end.
Active stylus 20 may include one or more ports 28 located at any
suitable location on outer body 22 of active stylus 20. Port 28 may
be configured to transfer signals or information between active
stylus 20 and one or more devices or power sources. Port 28 may
transfer signals or information by any suitable technology, such
as, for example, by universal serial bus (USB) or Ethernet
connections. Port 28 may transmit or receive signals wirelessly,
for example using BlueTooth or wireless fidelity (WiFi)
technologies. Although this disclosure describes and illustrates a
particular configuration of particular components with particular
locations, dimensions, composition and functionality, this
disclosure contemplates any suitable configuration of suitable
components with any suitable locations, dimensions, composition,
and functionality with respect to active stylus 20.
[0029] FIG. 3 illustrates an example internal components of example
active stylus 20. Active stylus 20 may include one or more internal
components, such as a controller 50, sensors 42, memory 44, or
power source 48. In particular embodiments, one or more internal
components may be configured to provide for interaction between
active stylus 20 and a user or between a device and a user. In
other particular embodiments, one or more internal components, in
conjunction with one or more external components described above,
may be configured to provide interaction between active stylus 20
and a user or between a device and a user. As an example and not by
way of limitation, interactions may include communication between
active stylus 20 and a device, enabling or altering functionality
of active stylus 20 or a device, or providing feedback to or
accepting input from one or more users.
[0030] Controller 50 may be a microcontroller or any other type of
processor suitable for controlling the operation of active stylus
20. Controller 50 may be one or more ICs--such as, for example,
general-purpose microprocessors, microcontrollers, PLDs, PLAs, or
ASICs. Controller 50 may include a processor unit, a drive unit, a
sense unit, and a storage unit. The drive unit may supply signals
to electrodes of tip 26 through center shaft 41. The drive unit may
also supply signals to control or drive sensors 42 or one or more
external components of active stylus 20. The sense unit may sense
signals received by electrodes of tip 26 through center shaft 41
and provide measurement signals to the processor unit representing
input from a device. The sense unit may also sense signals
generated by sensors 42 or one or more external components and
provide measurement signals to the processor unit representing
input from a user. The processor unit may control the supply and
timing of signals to the electrodes of tip 26 and process
measurement signals from the sense unit to detect and process input
from the device. The processor unit may also process measurement
signals from sensors 42 or one or more external components. The
storage unit may store programming for execution by the processor
unit, including programming for controlling the drive unit to
supply signals to the electrodes of tip 26, programming for
processing measurement signals from the sense unit corresponding to
input from the device, programming for processing measurement
signals from sensors 42 or external components to initiate a
pre-determined function or gesture to be performed by active stylus
20 or the device, and other suitable programming, where
appropriate. As an example and not by way of limitation,
programming executed by controller 50 may electronically filter
signals received from the sense unit. Although this disclosure
describes a particular controller 50 having a particular
implementation with particular components, this disclosure
contemplates any suitable controller having any suitable
implementation with any suitable components.
[0031] In particular embodiments, active stylus 20 may include one
or more sensors 42, such as touch sensors, gyroscopes,
accelerometers, contact sensors, or any other type of sensor that
detect or measure data about the environment in which active stylus
20 operates. Sensors 42 may detect and measure one or more
characteristic of active stylus 20, such as acceleration or
movement, orientation, contact, pressure on outer body 22, force on
tip 26, vibration, or any other suitable characteristic of active
stylus 20. As an example and not by way of limitation, sensors 42
may be implemented mechanically, electronically, or capacitively.
As described above, data detected or measured by sensors 42
communicated to controller 50 may initiate a pre-determined
function or gesture to be performed by active stylus 20 or the
device. In particular embodiments, data detected or received by
sensors 42 may be stored in memory 44. Memory 44 may be any form of
memory suitable for storing data in active stylus 20. In other
particular embodiments, controller 50 may access data stored in
memory 44. As an example and not by way of limitation, memory 44
may store programming for execution by the processor unit of
controller 50. As another example, data measured by sensors 42 may
be processed by controller 50 and stored in memory 44.
[0032] Power source 48 may be any type of stored-energy source,
including electrical or chemical-energy sources, suitable for
powering the operation of active stylus 20. In particular
embodiments, power source 48 may be charged by energy from a user
or device. As an example and not by way of limitation, power source
48 may be a rechargeable battery that may be charged by motion
induced on active stylus 20. In other particular embodiments, power
source 48 of active stylus 20 may provide power to or receive power
from the device. As an example and not by way of limitation, power
may be inductively transferred between power source 48 and a power
source of the device.
[0033] FIG. 4 illustrates an example active stylus 20 with an
example device 52. Device 52 may have a display (not shown) and a
touch sensor with a touch-sensitive area 54. Device 52 display may
be a liquid crystal display (LCD), a LED display, a LED-backlight
LCD, or other suitable display and may be visible though a cover
panel and substrate (and the drive and sense electrodes of the
touch sensor disposed on it) of device 52. Although this disclosure
describes a particular device display and particular display types,
this disclosure contemplates any suitable device display and any
suitable display types.
[0034] Device 52 electronics may provide the functionality of
device 52. As example and not by way of limitation, device 52
electronics may include circuitry or other electronics for wireless
communication to or from device 52, execute programming on device
52, generating graphical or other user interfaces (UIs) for device
52 display to display to a user, managing power to device 52 from a
battery or other power source, taking still pictures, recording
video, other suitable functionality, or any suitable combination of
these. Although this disclosure describes particular device
electronics providing particular functionality of a particular
device, this disclosure contemplates any suitable device
electronics providing any suitable functionality of any suitable
device.
[0035] In particular embodiments, active stylus 20 and device 52
may be synchronized prior to communication of data between active
stylus 20 and device 52. As an example and not by way of
limitation, active stylus 20 may be synchronized to device through
a pre-determined bit sequence transmitted by the touch sensor of
device 52. As another example, active stylus 20 may be synchronized
to device by processing the drive signal transmitted by drive
electrodes of the touch sensor of device 52. Active stylus 20 may
interact or communicate with device 52 when active stylus 20 is
brought in contact with or in proximity to touch-sensitive area 54
of the touch sensor of device 52. In particular embodiments,
interaction between active stylus 20 and device 52 may be
capacitive or inductive. As an example and not by way of
limitation, when active stylus 20 is brought in contact with or in
the proximity of touch-sensitive area 54 of device 52, signals
generated by active stylus 20 may influence capacitive nodes of
touch-sensitive area of device 52 or vice versa. As another
example, a power source of active stylus 20 may be inductively
charged through the touch sensor of device 52, or vice versa.
Although this disclosure describes particular interactions and
communications between active stylus 20 and device 52, this
disclosure contemplates any suitable interactions and
communications through any suitable means, such as mechanical
forces, current, voltage, or electromagnetic fields.
[0036] In particular embodiments, measurement signal from the
sensors of active stylus 20 may initiate, provide for, or terminate
interactions between active stylus 20 and one or more devices 52 or
one or more users, as described above. Interaction between active
stylus 20 and device 52 may occur when active stylus 20 is
contacting or in proximity to device 52. As an example and not by
way of limitation, a user may perform a gesture or sequence of
gestures, such as shaking or inverting active stylus 20, whilst
active stylus 20 is hovering above touch-sensitive area 54 of
device 52. Active stylus may interact with device 52 based on the
gesture performed with active stylus 20 to initiate a
pre-determined function, such as authenticating a user associated
with active stylus 20 or device 52. Although this disclosure
describes particular movements providing particular types of
interactions between active stylus 20 and device 52, this
disclosure contemplates any suitable movement influencing any
suitable interaction in any suitable way.
[0037] In particular embodiments, active stylus 20 may be used in a
hover configuration or mode. In hover mode, active stylus 20 is in
proximity to but is not touching device 52 (e.g. touch sensor 10 of
device 52). One potential benefit of using a stylus in a hover mode
is that a physical imprint (e.g., a fingerprint, grease print, or
vibration from touch) is not left on device 52; this may allow for
increased security in the use of device 52. As an example, a
gesture used while hovering may be used to unlock device 52 without
leaving any physical imprint (e.g., a pattern of fingerprints on
device 52) that may be detected. The distance that active stylus 20
hovers above or in proximity to device 52 may be determined either
by active stylus 20 or by device 52, including, for example, by
controller 12 or controller 50. As an example, active stylus 20 may
function well when it hovers in proximity to device 52 in distances
ranging between approximately (e.g., plus or minus 2 millimeters) 0
and 25 millimeters. In particular embodiments, the distance between
active stylus 20 and device 52 may be calculated between a
particular location on the body of active stylus 20 (e.g., the
point of active stylus tip 26) and a particular location on device
52 (e.g., a particular point on touch sensor 10).
[0038] In particular embodiments, the distance that active stylus
20 hovers in proximity to device 52 may be measured by laser
infrarometers, ultrasound, or sensors, any of which may be on
active stylus 20, on device 52, or on both active stylus 20 and
device 52. In particular embodiments, the hover distance may be
determined using touch sensor 10, without the need for additional
sensors on device 52. As discussed above, touch sensor 10 may
include an array of drive and sense electrodes forming an array of
capacitive nodes. As an example, the change in mutual capacitance
of each capacitive node in the array on touch sensor 10 may be
measured to determine stylus location, as the mutual capacitance
measured at each capacitive node will vary with stylus position in
the x-, y-, and z- (hover) directions with respect to device 52. In
particular, the measured change in mutual capacitance experienced
by each capacitive node in the array on touch sensor 10 will be
larger the closer that active stylus 20 is to the capacitive node
in any (x-,y-, or z-) direction. By examining the pattern of
changes in measured mutual capacitance values for the capacitive
nodes in the array on touch sensor 10 (either for the array as a
whole or, in certain embodiments, within subgroups of capacitive
nodes in the array), the hover distance of active stylus 20 may be
determined. As an example, by analyzing the pattern of capacitive
nodes that experienced a measured change in mutual capacitance (and
those capacitive nodes that did not, or that experienced a measured
change to a lesser extent), the location of active stylus 20 (e.g.,
the location of the active stylus tip 26) may be determined in the
x-y plane with respect to device 52.
[0039] By analyzing the amount of the measured change in mutual
capacitance for the array of capacitive nodes on touch sensor 10,
however, the location of active stylus 20 may be determined in the
z-direction with respect to device 52. That is, when the measured
change in mutual capacitance for the array of capacitive nodes on
touch sensor 10 is relatively large (an amount which may vary
between different products), then active stylus 20 may be
calculated to be closer in the z-direction (have a smaller hover
distance) to device 52. As another example, when the change in
mutual capacitance for the array of capacitive nodes on touch
sensor 10 is relatively small (an amount which may vary between
different products), then active stylus 20 may be calculated to be
farther in the z-direction (have a larger hover distance) to device
52. In other embodiments, the shape of the profile of those
capacitive nodes that experience a change in mutual capacitance may
also be analyzed to determine the location of active stylus 20 in
the z-direction. In particular embodiments, the hover distance may
be determined by controller 12. In other embodiments, the hover
distance may be determined by another processor using the response
from controller 12. In other embodiments, the hover distance may be
determined by controller 50 in stylus 20, based on signals or
capacitance changes measured at active stylus 20 via electrodes in
active stylus tip 26. In yet other embodiments, the hover distance
of a finger or a passive stylus may be determined in the same or
similar manner in which it is determined for active stylus 20,
because any suitable mutual-capacitance system will experience a
change in capacitance depending on the location of either a stylus
(whether active or passive) or a finger.
[0040] In particular embodiments, by analyzing the number of
capacitive nodes in the array on touch sensor 10 that experienced a
measured change in mutual capacitance, as well as the degree of
change of mutual capacitance, it may be possible to determine if a
stylus (whether active or passive) or finger is in proximity to
device 52, and if so, whether it is hovering or touching device 52.
In particular embodiments, one or more pre-determined thresholds
for measured changes in mutual capacitance may be set in controller
12, and these pre-determined thresholds may be associated with
distances (e.g., hover distances) from device 52. These
pre-determined thresholds may be set during a tuning or testing
period where a user is asked to bring a stylus (whether active or
passive) or a finger in a hover above device 52 and then in contact
with device 52. Controller 12 may then analyze the measured changes
in mutual capacitance that occur during this testing or tuning
period to set thresholds that may assist in determining whether a
stylus or finger is in proximity to device 52, and if so, whether
it is hovering above or in contact with device 52. For example,
controller 12 may determine that a particular measured change in
mutual capacitance (determined, e.g., during a testing period with
an active stylus) corresponds to the active stylus being a distance
of 10 mm above device 52.
[0041] In particular embodiments, pre-determined thresholds (e.g.,
set during a tuning or testing period) may be used to determine
whether a stylus or finger is present, whether it is hovering above
device 52, or whether it is touching device 52. In yet other
embodiments, analyzing the number of capacitive nodes in the array
on touch sensor 10 that experienced a measured change in mutual
capacitance, as well as the degree of change of mutual capacitance
may be used to determine whether a stylus or finger is present,
whether it is hovering above device 52, or whether it is touching
device 52. As an example, if a relatively large change in mutual
capacitance is measured, but the change is limited to a relatively
small number of nodes of the array on touch sensor 10, the
controller 12 may determine that an active stylus is touching
device 52. As another example, if a relatively large change in
mutual capacitance is measured, and the change is measured over a
relatively large number of nodes of the array on touch sensor 10,
the controller 12 may determine that a finger is touching device
52, as a finger generally has a larger profile than, for example, a
stylus. As yet another example, if a relatively medium or small
change in mutual capacitance is measured, and the change is limited
to a relatively small number of nodes of the array on touch sensor
10, the controller 12 may determine that a passive stylus is
touching device 52. Finally, if a relatively small change in mutual
capacitance is measured, but the change is measured over a
relatively large number of nodes of the array on touch sensor 10,
the controller 12 may determine that a finger is hovering over
device 52. In particular embodiments, both a stylus and a finger
may be used at the same time with device 52, and separate (but
potentially overlapping) portions of touch sensor 10 may provide
data to controller 12 to make determinations about whether a stylus
or finger (or both) is present, if it is hovering above device 52,
or whether it is in contact with device 52.
[0042] By measuring hover distance, a user may hover (with active
stylus 20 or a finger) and use device 52 without contacting device
52. As an example, a user can use device 52 (e.g. touch sensor 10)
as a piano. As another example, a user may use active stylus 20 (or
a finger) to make a gesture (e.g., a signature) while hovering that
may be used to unlock or authenticate active stylus 20. By
unlocking or authenticating device 52 using a three-dimensional
gesture as opposed to a two-dimensional gesture (done by contacting
device 52, perhaps leaving an imprint), more security can be
provided to the user of device 52 and active stylus 20. That is, a
three-dimensional gesture (using the x-, y-, and z-directions with
respect to device 52) may be harder to copy than a two-dimensional
gesture (using only the x- and y-directions), and, additionally, a
gesture completed while hovering will not leave an imprint on
device 52 that may be intercepted. As another example, the user may
use active stylus 20 while hovering for gaming purposes.
[0043] The determination of hover distance (e.g., the location of
active stylus 20 or a finger in the z-direction with respect to
device 52) may be used for a variety of purposes. By way of
example, the determination of hover distance may be used to
determine whether a user is making a gesture (and if so, which
gesture) or whether there has been a change in orientation in
active stylus 20 with respect to device 52 (e.g., allowing active
stylus 20 to be used as a joystick). The determination of the hover
distance of active stylus 20 may be used to decide whether to
employ high voltage signals for signal transmission (on either
device 52 or active stylus 20) to provide for better
signal-to-noise ratios. As another example, the hover distance may
be used in conjunction with algorithms for dynamic configuration of
electrodes in active stylus tip 26 so that when it is determined
that active stylus 20 is hovering beyond a particular distance from
device 52, electrodes in active stylus tip 26 should be
reconfigured in a particular manner. Similarly, the hover distance
may be used to dynamically adjust signal thresholds used by active
stylus 20 or device 52 to reduce the effects of noise.
[0044] In FIG. 5A, active stylus 20 is near touch-sensitive display
54 of touch-sensitive device 52. Tip 26 of active stylus 20 is
located a distance D1 away from touch-sensitive display 54. As an
example, D1 may be between approximately 0 and 25 millimeters. One
or more electrodes in tip 26 may, in particular embodiments,
receive voltage signals from active stylus 20 and output voltage
signals to touch-sensitive device 52. Conductive material, such as
drive and sense lines near touch-sensitive display 54, and
associated electronics in touch-sensitive device 52 may sense these
voltage signals. As an example, voltage signals produced by
electrodes in tip 26 alter the net charge present on sense lines in
the proximity of tip 26, communicating information about the
location of active stylus 20 in directions parallel to
touch-sensitive display 52. The net charge present on sense lines
also depends on the distance D1 that active stylus tip 26 is from
touch-sensitive display 54, communicating information to
touch-sensitive device 52 about the location of active stylus 20 in
directions perpendicular to touch-sensitive display 54. In
particular embodiments, motion of tip 26 relative to
touch-sensitive display 54 is detected by touch-sensitive device 52
through changes in the net charge on sense lines as active stylus
20 moves. In particular embodiments, motion of tip 26 relative to
touch-sensitive display 54 is determined by correlating information
about the location of active stylus 20 with the point in time
active stylus 20 had been at that location. In particular
embodiments, active stylus 20 may be oriented at any suitable angle
with respect to touch-sensitive display 52. As an example, FIG. 5B
illustrates the body of active stylus 20 contacting touch-sensitive
display 54 and tip 26 separated from touch-sensitive display 54 by
a distance D2.
[0045] FIG. 6 illustrates an example method for determining the
hover distance of an active stylus (e.g., active stylus 20). The
method begins at step 600, when a change in capacitance in one or
more capacitive nodes of a touch-sensor (e.g., touch sensor 10) of
a device (e.g., device 52) is detected in response to a stylus
being in proximity to (but not touching) the device. It should be
noted that in particular embodiments, a signal need not be actively
transmitted for hover distance to be calculated, as a change in
capacitance may still be detected even with a passive object such
as a finger. The change in capacitance may be detected in the
mutual capacitance outputs of one or more of the capacitive nodes
in an array on a touch-sensitive area (e.g., touch sensor 10) of
device 52. At step 610, this change in capacitance is analyzed to
determine the hover distance of the stylus. As discussed above, it
may be possible to analyze the magnitude of the pattern of change
in mutual capacitance across the array of capacitive nodes to
determine whether active stylus 20 is closer or farther from device
52. In particular embodiments, the steps illustrated in FIG. 6 may
be repeated any number of times. Although this disclosure describes
and illustrates particular steps of the method of FIG. 6 as
occurring in a particular order, this disclosure contemplates any
suitable steps of the method of FIG. 6 occurring in any suitable
order. Furthermore, although this disclosure describes and
illustrates particular components, devices, or systems carrying out
particular steps of the method of FIG. 6, this disclosure
contemplates any suitable combination of any suitable components,
devices, or systems carrying out any suitable steps of the method
of FIG. 6.
[0046] Herein, reference to a computer-readable non-transitory
storage medium or media may include one or more semiconductor-based
or other integrated circuits (ICs) (such as, for example,
field-programmable gate arrays (FPGAs) or application-specific ICs
(ASICs)), hard disk drives (HDDs), hybrid hard drives (HHDs),
optical discs, optical disc drives (ODDs), magneto-optical discs,
magneto-optical drives, floppy disks, floppy disk drives (FDDs),
magnetic tapes, holographic storage media, solid-state drives
(SSDs), RAM-drives, SECURE DIGITAL cards, SECURE DIGITAL drives,
any another suitable computer-readable non-transitory storage
media, or a suitable combination of these, where appropriate. A
computer-readable non-transitory storage medium may be volatile,
non-volatile, or a combination of volatile and non-volatile, where
appropriate.
[0047] Herein, "or" is inclusive and not exclusive, unless
expressly indicated otherwise or indicated otherwise by context.
Therefore, herein, "A or B" means "A, B, or both," unless expressly
indicated otherwise or indicated otherwise by context. Moreover,
"and" is both joint and several, unless expressly indicated
otherwise or indicated otherwise by context. Therefore, herein, "A
and B" means "A and B, jointly or severally," unless expressly
indicated otherwise or indicated otherwise by context.
[0048] This disclosure encompasses all changes, substitutions,
variations, alterations, and modifications to the example
embodiments herein that a person having ordinary skill in the art
would comprehend. Moreover, reference in the appended claims to an
apparatus or system or a component of an apparatus or system being
adapted to, arranged to, capable of, configured to, enabled to,
operable to, or operative to perform a particular function
encompasses that apparatus, system, component, whether or not it or
that particular function is activated, turned on, or unlocked, as
long as that apparatus, system, or component is so adapted,
arranged, capable, configured, enabled, operable, or operative.
* * * * *