U.S. patent application number 16/531729 was filed with the patent office on 2020-03-26 for unitary sensor and haptic actuator.
The applicant listed for this patent is Immersion Corporation. Invention is credited to Juan Manuel CRUZ HERNANDEZ, Abdelwahab HAMAM, Vahid KHOSHKAVA.
Application Number | 20200097089 16/531729 |
Document ID | / |
Family ID | 60888071 |
Filed Date | 2020-03-26 |
United States Patent
Application |
20200097089 |
Kind Code |
A1 |
KHOSHKAVA; Vahid ; et
al. |
March 26, 2020 |
UNITARY SENSOR AND HAPTIC ACTUATOR
Abstract
A bi-functional apparatus for sensing touch and delivering a
haptic signal. The bi-functional apparatus comprises first and
second electrodes. The first electrode provides a haptic interface
for delivering an electrostatic force and has a top surface and a
bottom surface. A dielectric insulator covers the top surface of
the first electrode. A sensor is positioned between the bottom
surface of the first electrode and the second electrode. The sensor
selectively provides electrical conductivity between the first and
second electrodes in response to at least a threshold amount of
pressure exerted against the dielectric insulator. A method of
sensing touch and delivering a haptic signal with a single device.
The method comprises receiving an input at a touch surface of a
dielectric insulator layered over a first electrode; in response to
receiving the input at the touch surface, increasing the electrical
conductivity of a sensor positioned between the first electrode and
a second electrode; in response to increasing electrical
conductivity of the sensor, conducting an electrical current
between the first and second electrodes; and in response to
conducting an electrical current between the first and second
electrodes, applying a haptic drive signal to the first electrode,
the haptic drive signal creating an electrostatic force in the
dielectric insulator.
Inventors: |
KHOSHKAVA; Vahid; (Montreal,
CA) ; HAMAM; Abdelwahab; (San Jose, CA) ; CRUZ
HERNANDEZ; Juan Manuel; (Montreal, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Immersion Corporation |
San Jose |
CA |
US |
|
|
Family ID: |
60888071 |
Appl. No.: |
16/531729 |
Filed: |
August 5, 2019 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
15392784 |
Dec 28, 2016 |
10416768 |
|
|
16531729 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/0447 20190501;
G06F 3/044 20130101; G06F 3/016 20130101; G06F 3/0445 20190501;
G06F 2203/04102 20130101; G06F 3/0414 20130101; G06F 3/0416
20130101 |
International
Class: |
G06F 3/01 20060101
G06F003/01; G06F 3/041 20060101 G06F003/041; G06F 3/044 20060101
G06F003/044 |
Claims
1. (canceled)
2. A method of rendering a haptic effect on a display, the method
comprising: receiving an input on the display, a touch surface of
the display including a protective layer on a first electrode;
increasing electrical conductivity of a sensor positioned between
the first electrode and a second electrode; conducting an
electrical current between the first electrode and the second
electrode; and applying a haptic drive signal to the first
electrode to render the haptic effect on the display, the haptic
drive signal generating the haptic effect in response to the
input.
3. The method of claim 2, wherein the display comprises a flexible
display configured to be applied to a non-flat surface.
4. The method of claim 2, wherein the protective layer and the
first electrode are flexible and configured to bend in response to
a first pressure applied by the input and to exert a second
pressure on the sensor.
5. The method of claim 2, wherein the display comprises a curved
glass.
6. The method of claim 2, wherein the first electrode is a haptic
output device configured to render an electrostatic force or
transcutaneous electrical stimulation.
7. The method of claim 2, wherein the protective layer is a
dielectric insulator layer.
8. The method of claim 2, wherein the display is applied to a
tablet, a laptop, a smartphone or wearable device.
9. A device comprising: a processor; a display; and a memory
storing a program for execution by the processor, the program
including instructions for: receiving an input on the display, a
touch surface of the display including a protective layer on a
first electrode; increasing electrical conductivity of a sensor
positioned between the first electrode and a second electrode;
conducting an electrical current between the first electrode and
the second electrode; and applying a haptic drive signal to the
first electrode to render a haptic effect on the display, the
haptic drive signal generating the haptic effect in response to the
input.
10. The device of claim 9, wherein the display comprises a flexible
display configured to be applied to a non-flat surface.
11. The device of claim 9, wherein the protective layer and the
first electrode are flexible and configured to bend in response to
a first pressure applied by the input and to exert a second
pressure on the sensor.
12. The device of claim 9, wherein the display comprises a curved
glass.
13. The device of claim 9, wherein the first electrode is a haptic
output device configured to render an electrostatic force or
transcutaneous electrical stimulation.
14. The device of claim 9, wherein the protective layer is a
dielectric insulator layer.
15. The device of claim 9, wherein the display is applied to a
tablet, a laptop, a smartphone or wearable device.
16. A non-transitory computer readable storage medium storing a
program configured to be executed by a processor, the program
comprising instructions for: receiving an input on the display, a
touch surface of the display including a protective layer on a
first electrode; increasing electrical conductivity of a sensor
positioned between the first electrode and a second electrode;
conducting an electrical current between the first electrode and
the second electrode; and applying a haptic drive signal to the
first electrode to render a haptic effect on the display, the
haptic drive signal generating the haptic effect in response to the
input.
17. The non-transitory computer readable storage medium of claim
16, wherein the display comprises a flexible display that is
configured to be applied to a non-flat surface.
18. The non-transitory computer readable storage medium of claim
16, wherein the protective layer and the first electrode are
flexible and configured to bend in response to a first pressure
applied by the input and to exert a second pressure on the
sensor.
19. The non-transitory computer readable storage medium of claim
16, wherein the display comprises a curved glass.
20. The non-transitory computer readable storage medium of claim
16, wherein the first electrode is a haptic output device
configured to render an electrostatic force or transcutaneous
electrical stimulation.
21. The non-transitory computer readable storage medium of claim
16, wherein the display is applied to a tablet, a laptop, a
smartphone or wearable device.
Description
PRIORITY APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/392,784, filed on Dec. 28, 2016, which has
been incorporated herein by reference in its entirety.
TECHNICAL DESCRIPTION
[0002] This patent relates to sensors and haptic actuators, and
more particularly to unitary SENSORS AND HAPTIC ACTUATORS.
BACKGROUND
[0003] Haptic effects are used to enhance the interaction of an
individual with an electronic device. Haptic effects enable the
user to experience a touch sensation, which is typically generated
by an actuator embedded in the device. Recent innovations have
enabled the development of haptic actuators that generate an
electrostatic force (ESF), which creates a capacitive coupling
between a charged electrode and the electrically conductive tissues
of a human. This capacitive coupling stimulates the skin and
provides a tactile sensation. However, these ESF haptic actuators
require a high voltage signal (e.g., 100-2000 Volts or higher) to
generate an electrostatic force that is large enough to be felt by
a user. Generating and delivering such a high voltage signal
requires high voltage amplifiers, high voltage electrical
components, and significant battery resources. These components are
expensive and bulky, which results in packaging problems as
manufacturers try to reduce the size of their components and
devices.
[0004] Additionally, many devices having haptic actuators require a
sensor to determine a condition upon which to deliver a haptic
effect. The requirement of a separate sensor adds even more
expense, complexity, and bulk to devices and systems that include
haptic actuators.
[0005] Another issue with prior art haptic actuators, especially
actuators that deliver haptic effects using electrostatic forces,
is that they are typically rigid and do not lend themselves to
sensing pressure. Nor do they have the flexibility to adapt to
flexible or irregular substrates. These prior art devices have
limited applications.
SUMMARY
[0006] One aspect of this document relates to a bi-functional
apparatus for sensing touch and delivering a haptic signal. The
bi-functional apparatus comprises first and second electrodes. The
first electrode provides a haptic interface for delivering an
electrostatic force and has a top surface and a bottom surface. A
dielectric insulator covers the top surface of the first electrode.
A sensor is positioned between the bottom surface of the first
electrode and the second electrode. The sensor selectively provides
electrical conductivity between the first and second electrodes in
response to at least a threshold amount of pressure exerted against
the dielectric insulator.
[0007] Another aspect is a bi-functional apparatus for sensing
touch and delivering a haptic signal. The bi-functional apparatus
comprises first and second electrodes. The first electrode provides
a haptic interface for delivering an electrostatic force and has a
top surface and a bottom surface. A dielectric insulator covers the
top surface of the first electrode. A sensor is positioned between
the bottom surface of the first electrode and the second electrode.
The sensor selectively provides electrical conductivity between the
first and second electrodes in response to at least a threshold
amount of pressure exerted against the dielectric insulator. The
sensor comprises a quantum tunneling composite. The combined first
and second electrodes, dielectric insulator, and sensor are
flexible and have a combined thickness in the range of about 0.1 mm
to about 1 mm.
[0008] Another aspect is a bi-functional apparatus for sensing
touch and delivering a haptic signal. The bi-functional apparatus
comprises first, second, and third electrodes. The first electrode
provides a haptic interface for delivering an electrostatic force
and has a top surface and a bottom surface. A dielectric insulator
covers the top surface of the first electrode. An electrical
insulator is positioned between the bottom surface of the first
electrode and the second electrode. A sensor is positioned between
the second electrode and the third electrode. The sensor
selectively provides electrical conductivity between the second and
third electrodes in response to at least a threshold amount of
pressure exerted against the dielectric insulator.
[0009] Another aspect is a method of sensing touch and delivering a
haptic signal with a single device. The method comprises receiving
an input at a touch surface of a dielectric insulator layered over
a first electrode; in response to receiving the input at the touch
surface, increasing the electrical conductivity of a sensor
positioned between the first electrode and a second electrode; in
response to increasing electrical conductivity of the sensor,
conducting an electrical current between the first and second
electrodes; and in response to conducting an electrical current
between the first and second electrodes, applying a haptic drive
signal to the first electrode, the haptic drive signal creating an
electrostatic force in the dielectric insulator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a top isometric view of a unitary haptic
device.
[0011] FIG. 2 is a cross-sectional view of the unitary haptic
device illustrated in FIG. 1 taken along line 2-2.
[0012] FIG. 3 is a cross-sectional view illustrating operation of
the unitary haptic device shown in FIGS. 1 and 2 delivering an
electrostatic force.
[0013] FIGS. 4A and 4B is a cross-sectional view illustrating
operation of an embodiment of a sensor element in the unitary
haptic device shown in FIGS. 1 and 2.
[0014] FIGS. 5A-5C is a circuit and a cross-sectional view
illustrating operation of the unitary haptic actuator shown in
FIGS. 1 and 2.
[0015] FIGS. 6A and 6B is a circuit and a cross-sectional view
illustrating an alternative operation of the unitary haptic device
shown in FIGS. 1 and 2.
[0016] FIG. 7 is a cross-sectional view illustrating an alternative
embodiment of the unitary haptic device shown in FIGS. 1 and 2.
[0017] FIG. 8 is an isometric view illustrating a user interface
formed with a plurality of the unitary haptic devices shown in
FIGS. 1 and 2 or FIG. 7.
[0018] FIG. 9 is a functional block diagram of a control circuit
for controlling unitary haptic devices illustrated in FIGS.
1-8.
DETAILED DESCRIPTION
[0019] Various embodiments will be described in detail with
reference to the drawings, wherein like reference numerals
represent like parts and assemblies throughout the several views.
Reference to various embodiments does not limit the scope of the
claims attached hereto. Additionally, any examples set forth in
this specification are not intended to be limiting and merely set
forth some of the many possible embodiments for the appended
claims.
[0020] Whenever appropriate, terms used in the singular also will
include the plural and vice versa. The use of "a" herein means "one
or more" unless stated otherwise or where the use of "one or more"
is clearly inappropriate. The use of "or" means "and/or" unless
stated otherwise. The use of "comprise," "comprises," "comprising,"
"include," "includes," "including," "has," and "having" are
interchangeable and not intended to be limiting. The term "such as"
also is not intended to be limiting. For example, the term
"including" shall mean "including, but not limited to."
[0021] In general terms, this patent document relates to a unitary
haptic device for delivering a haptic effect. The unitary haptic
device is bi-functional and operates as both a touch sensor and a
haptic actuator. A haptic effect can be any type of tactile
sensation delivered to a person. In some embodiments, the haptic
effect embodies information such as a cue, notification, feedback
or confirmation of a user's interaction with a haptic-enabled
article, or a more complex message or other information. In
alternative embodiments, the haptic effect can be used to enhance a
user's interaction with a device by simulating a physical property
or effect such as friction, flow, and detents.
[0022] Referring now to FIGS. 1 and 2, a possible embodiment of a
unitary haptic device 100 comprises first and second electrodes 102
and 104. A sensor element 106 is positioned between the first and
second electrodes 102 and 104. A protective layer 110 is positioned
over the first electrode 102 and provides a touch surface 112. As
discussed in more detail herein, the first electrode 102, second
electrode 104, and sensor element 106 cooperate to sense when a
user or object touches the touch surface 112, or in some embodiment
moves proximal to the touch surface 112. Also as discussed in more
detail herein, the first electrode 102 operates as a haptic
actuator to deliver a haptic effect using electrostatic force (ESF)
or transcutaneous electrical stimulation (TES). Other embodiments,
however, can include structure additional to, or even in place of,
the first electrode 102 to operate as the haptic actuator.
[0023] In at least some embodiments, the protective layer 110 is an
electrical insulator formed with a dielectric material. Examples of
dielectric materials that can be used to form the protective layer
110 include silicon dioxide (SiO.sub.2); silicon nitride
(SiO.sub.3N.sub.4); parylene; or composite coatings which can
include organic or inorganic material. The dielectric material can
be applied to the first electrode 102 using any suitable technical
including deposition and sputtering. The sensor element 106 is a
sensor that detects touch or, in some embodiments, close proximity
to the touch surface 112. Examples of sensor elements 106 that
detect touch include quantum tunneling composites, piezoresistive
cells, photoresistors, and other materials that change electrical
properties such as conductivity, resistance, inductance, or
capacitance when exposed to or deprived of an external force or
stimulation such as pressure or light.
[0024] In at least some embodiments, the first electrode 102 covers
the entire surface of the sensor element 106. In alternative
embodiments, a plurality of first electrodes 102, which are
electrically isolated from each other, can be applied to the
surface of the sensor element 106 in a pattern such as parallel
ribbons, circles, triangles, an array of squares, an array of other
shapes, and other geometric patterns and shapes.
[0025] Additionally, in some embodiments, the protective layer 110
and the first electrode 102 are flexible so that they can bend
under pressure and exert pressure against the sensor element 106.
In other embodiments, the entire unitary haptic device 100 is
flexible. An advantage of the entire unitary haptic device 100
being flexible is that it can be applied to and conform to
substrates having non-flat or otherwise irregular surface. For
example, the unitary haptic device could be applied to the surface
of universal touch pads, flexible displays, displays having curved
glass, buttons, or even hand grips. It also makes manufacturing
easier because the bendable or flexible unitary haptic device 100
may be applied more readily to substrates that are out of tolerance
or have other defects in their surface.
[0026] The unitary haptic device 100 has an overall depth in the
range of about 0.1 mm to about 1 mm, although other embodiments can
have an overall depth that is smaller or greater than this range.
This depth provides a thin, bi-functional sensor and haptic
actuator that can be applied to a variety of different devices
having a variety of different purposes. This thin depth of the
unitary haptic device 100 is enabled by factors such as the overall
structure of the unitary haptic device 100 and the type of
materials used for each layer. The protective layer 110 has a
thickness in the range of about 0.1.mu. to about 1.5.mu.. In
alternative embodiments, the protective layer 110 has a thickness
in the range of about 0.5.mu. to about 1.mu.. The thickness of the
protective layer 110 depends on factors such as the material that
is used to form the layer 110. If the protective layer 110 is
formed with a dielectric material, the thickness of the layer 110
also depends on the desired dielectric constant for the layer 110;
the thicker the layer 110 the higher the voltage that will be
applied to the electrode to generate a haptic effect. The first and
second electrodes 102 and 104 have a thickness in the range of
about 20 nm to about 0.5.mu.. In alternative embodiments, the first
and second electrode could have a thickness in the range of about
0.1 mm to about 1 mm. In yet other embodiments, the first and
second electrodes have a thickness in the range of about 20 nm to
about 1 mm. The sensor element 106 has a thickness in the range of
about 0.1 mm and above. In alternative embodiments, the sensor has
a thickness in the range of about 0.1 mm to about 1 mm. The
thickness of the electrode element may depend on a variety of
factors such as the material used to form the electrodes 102 and
104, the manufacturing process used to form the electrodes 102 and
104, and desired reliability and performance characteristics of the
electrode 102 and 104. The thickness of the sensor element 106 may
depend on a variety of factors such as the type of sensor being
used, characteristics of electrical signals being applied to the
unitary haptic device 100 such as voltage and current, the desired
sensitivity of the sensor element 106, the resolution of the sensor
element 106, the threshold value of the sensor element 106, and
other performance characteristics for the unitary haptic device
100. Each of the individual layers 102, 104, 106, and 110 in
alternative embodiments of the unitary haptic device 100 can have a
thickness that is smaller or greater than the ranges provided
above. Additionally, the actual depth of the unitary haptic device
100 and each of the individual layers 102, 104, 106, 110 may depend
on the factors noted herein and on other factors. The depth and
thickness also may depend on balancing performance of the unitary
haptic device 100, design criteria, manufacturing constrains, and
cost.
[0027] The unitary haptic devices disclosed herein and embodiment
thereof have the flexibility to be implemented in different ways
and have different embodiments. For example, the unitary haptic
devices can be controlled to switch operation between a sensing
mode and a haptic-delivery mode. Alternatively, some embodiment of
the unitary haptic devices disclosed herein can simultaneously
sense touch and deliver a haptic effect. Additionally, the unitary
haptic device disclosed herein can embody alternative actuators to
deliver haptic effect using techniques other than ESF and TES.
Other types of actuators that can be embodied in a unitary haptic
device as disclosed herein include piezoelectric cells, smart
materials such as electroactive polymers, microfiber composites,
shape memory polymers and metals, and any other material that
vibrates or changes shape upon receiving external stimulation such
as an electrical potential, electrical current, electrical field,
magnetic field, or temperature change.
[0028] As illustrated in FIG. 3, when ESF is used to deliver a
haptic effect as illustrated herein, an actuator drive circuit 132
is in electrical communication with the second electrode. The
actuator drive circuit has a signal generator 133 and an amplifier
135. The signal generator 133 generates a signal having an
alternating waveform and the amplifier 135 amplifies the signal to
generate a haptic drive signal to apply to the first electrode 102
and create a capacitance 134 between the electrode 102 and the
user's 116 finger, or other body part contacting the touch surface
112. The user's 116 skin provides a ground 114 relative to the
first electrode 102.
[0029] In these embodiments, the protective layer 110 is an
electrical insulator formed with a dielectric material, and the
electrical potential causes charges in the protective layer 110 to
separate, with charges of one polarity (e.g., positive) along the
top or touch surface 112 of the protective layer 110 proximal to
the user's 116 skin and charges of the opposite polarity (e.g.,
negative) to move along the bottom surface of the protective layer
110 proximal to the first electrode 102. In turn, charges having a
polarity opposite to those along the touch surface 112 of the
protective layer 110 (e.g., negative) accumulate in the portion of
the user's 116 skin adjacent to the first electrode 102 and against
the insulator 110. The opposite polarity generates a force that
urges the skin toward the touch surface 112 of the dielectric
insulator 110 thus creating a tactile sensation in the skin
116.
[0030] When an alternating signal (e.g., one alternating between
positive and negative) is applied to the first electrode 102, the
charges in the electrode 102 alternate between positive and
negative. The alternating charges in the first electrode 102 in
turn causes the charges proximal the touch surface 112 and bottom
surface of the insulator 110 to alternative between positive and
negative, which in turn causes the charges accumulating in the
user's 116 skin adjacent to the first electrode 102 to alternate
between positive and negative. This alternating polarity will cause
the user's 116 skin to be alternatively forced toward the first
electrode 102 and then released. If the user 116 is holding their
fingertip or other portion of their body steady against the touch
surface 112, the sensation of their skin moving up and down is felt
as a vibration in the skin 116 creating a static haptic effect. If
the user 116 is moving their fingertip, or other body part, along
the touch surface 112, the skin will still vibrate, but it will
create a dynamic haptic effect such as a sensation of friction,
flow, or movement. In exemplary embodiments, the amplitude of the
haptic drive signal applied to the first electrode 102 is in the
range from about 50 V and higher. In exemplary embodiments for
delivering a static ESF, the amplitude of the haptic drive signal
is in the range from about 50 V to about 2,000 V. In exemplary
embodiments when delivering a dynamic ESF, the amplitude of the
haptic drive signal is in the range of about 500 V to about 2,000
V. Additionally, the stronger the haptic drive signal, the more
likely the resulting ESF will be strong enough that a user will
feel the haptic effect even with distractions in the environment
around them. For most users, environments, and hardware
configurations, a haptic drive signal having an amplitude of 500 V
or higher will provide a haptic effect strong enough to feel in
most situations and environments. Although certain ranges for the
haptic drive signal are provided, other embodiments could use
signals higher or lower than the ranges provided herein.
[0031] In embodiments that deliver haptic effects using TES, a
small electrical current flows from the first electrode 102,
through the protective layer 110, and into the user's 116 skin. In
these embodiments, the protective layer 110 is formed with a
material that has at least a limited amount of conductance to allow
very low levels of electrical current to flow through it. The
charges passing into the user's 116 skin stimulates receptors in
the user's 116 nerves causing a tingling sensation, which delivers
the haptic effect. In exemplary embodiments, the level of
electrical current that flows from the first electrode 102 and into
the user's 116 skin is in the range from about 1 mA to about 4 mA.
In another exemplary embodiment, the level of current that flows
from the first electrode 102 and into the user's 116 skin is in the
range from about 2.5 mA to about 4 mA, which provides TES strong
enough that a user 116 will feel the haptic effect even with
distractions in the environment around them.
[0032] FIGS. 4A and 4B illustrate operation of an embodiment of the
sensor element 106 in the unitary haptic device 100 that is formed
with a quantum tunneling composite, which is a material that
changes its electrical conductance (or electrical resistance) based
on changes to the amount of compressive force applied against it.
Quantum tunneling composites comprise a combination of conductive
particles 117 such as metals and non-conductive material such as
elastomeric binders. The conductive particles 117 are disbursed
throughout the composite. When a quantum tunneling composite is not
compressed, the conductive particles are relatively far apart so
they have a relatively low conductance and high resistance to an
electrical current. However, as compression of a quantum tunneling
composite increases, the conductive particles are forced closer
together and the conductivity of the quantum tunneling composite
increases enabling electrical current to flow. The quantum
tunneling composite functions as a variable resistor in which the
resistance of the composite changes as a function of the pressure
applied to it. The greater the pressure, the greater the
conductance of the material and the lower the resistance of the
material.
[0033] A quantum tunneling composite can be a polymer-based ink or
gel and can be opaque or transparent. The quantum tunneling
composite can be printed onto the second electrode 104, although
the quantum tunneling composite can be applied to the second
electrode 104 using alternative manufacturing techniques. In these
embodiments, at least the protective layer 110 and first electrode
102 are flexible and can bend.
[0034] As illustrated in FIG. 4A, when there is no pressure exerted
against the touch surface 112, the first electrode 102 and sensor
element 106 do not bend, compress, or otherwise deform. In this
state, the conductive particles 117 in the quantum tunneling
composite are relatively far apart and provide a low conductance
for, and high resistance to, the flow of electrons from one
particle 117 to another. In this embodiment of a quantum tunneling
composite, only a relatively low level of electrical current can
flow through the depth of the sensor element 106. In alternative
embodiments, however, the quantum tunneling composite operates as
an electrical insulator so substantially no electrical current can
flow entirely through the quantum tunneling composite and the
electrons are prevented from flowing from the second electrode 104
to the first electrode 102.
[0035] As illustrated in FIG. 4B, when a user touches and exerts
force against the touch surface 112, the protective layer 110 and
the first electrode 102 deform and compress the sensor element 106.
Compressing the sensor element 106 with enough force causes the
conductive particles 117 in the quantum tunneling composite to move
relatively close enough together so that electrons can move from
conductive particle 117 to conductive particle 117. The
conductivity of the quantum tunneling composite in the sensor
element 106 increases, allowing electrons and hence electrical
current 130 to flow from the second electrode 104 to the first
electrode 102.
[0036] FIGS. 5A-5C illustrate operation of the unitary haptic
device 100 in a control circuit that automatically switches
operation of the unitary haptic device between a sensing mode and a
haptic-delivery mode. In the illustrated embodiment, the sensor
element 106 is formed with a quantum tunneling composite.
[0037] In this embodiment, a voltage divider 118 has first and
second resistances or impedances connected in series. The first
resistance 120 is in electrical series between a power supply,
V.sub.in, and a node 124. The second resistance is provided by the
sensor element 106 and is in electrical series between the node 124
and ground 122 through the first and second electrodes 102 and 104.
The node 124 is electrically connected to a controller 162
(discussed in more detail herein), which monitors the output
voltage, V.sub.out, at the node 124. A sensor switch 126 is a
single pole, double throw switch that has a common terminal
electrically connected to the first electrode 102, a first switched
terminal electrically connected to the actuator drive circuit 132,
and a second switched terminal electrically connected to the
voltage divider 118. The sensor switch 126 switches electrical
continuity for the first electrode 102 between the actuator drive
circuit 132, and the input voltage, V.sub.in, for the voltage
divider 118. When the sensor switch 126 is switched to the second
terminal, the first electrode 102 forms a part of and completes the
voltage divider 118.
[0038] The voltage divider 118 forms a sensor circuit. Alternative
embodiments can use circuits other than a voltage divider to
determine when sensor element 106 has responded to a physical
stimulation by changing a characteristic such as resistance or some
other characteristic. The actuator drive circuit 132 is in
electrical communication with the first electrode, and as discussed
herein, the controller 162 controls when the actuator drive circuit
132 applies a haptic drive signal to the electrode 102.
[0039] Referring now to FIG. 5A, when the unitary haptic device 100
is being operated in a sensing mode, the sensor switch 126 is
switched to provide continuity between the first electrode 102 and
the input voltage, V.sub.in. When the sensor switch 126 is in this
position, the first electrode is connected to and completes the
voltage divider 118. The sensor element 106 is not being
compressed, or is being lightly compressed, so that the quantum
tunneling composite has a relatively high electrical resistance and
only a small electrical current can flow between the first and
second electrodes 102 and 104 (e.g., FIG. 4A) to ground 122. In
this uncompressed state, the controller 162 controls the actuator
drive circuit 132 so that it does not deliver a haptic drive signal
to the first electrode 102 at the same time the voltage divider is
electrically connecting the input voltage, V.sub.in, to the first
electrode. In this state, the output voltage, V.sub.out, at node
124 is slightly lower than the input voltage, V.sub.in. In
embodiments where the quantum tunneling composite is an open
circuit when uncompressed, V.sub.out will equal V.sub.in.
[0040] Referring now to FIG. 5B, when a person presses against the
touch surface 112 and the sensor element 106 compresses enough to
start decreasing the electrical resistance of the quantum tunneling
composite between the first and second electrodes 102 and 104 (as
shown in FIG. 4B), the value of the output voltage V.sub.out, at
the node 124 will fall relative to the value it had when the sensor
element 106 and quantum tunneling composite are in the uncompressed
state as illustrated in FIG. 5A. In this transitional state, the
controller 162 continues to control the actuator drive circuit 132
so that it does not deliver a haptic drive signal to the first
electrode 102.
[0041] Referring now to FIG. 5C, when the sensor element 106 is
compressed enough to sufficiently decrease the resistance of the
quantum tunneling composite so the output voltage, V.sub.out, at
the node 124 falls below a threshold level, the controller 162 will
switch the sensor switch 126 to disconnect the first electrode 102
from the input voltage, V.sub.in, and connect the first electrode
102 to the actuator drive circuit 132. When the sensor switch 126
is in this position, the first electrode 102 is not connect to and
does not form a part of the voltage divider 118. The unitary haptic
device 100 is then switched from the sensing mode to the
haptic-delivery mode. The controller 162 then controls the actuator
drive circuit 132 to generate a haptic drive signal and apply it to
the first electrode 102. Because the haptic drive signal can have a
very high voltage in some embodiments, controlling the sensor
switch 126 to disconnect the first electrode 102 from the voltage
divider 118 also isolates the controller 162 from the output of the
actuator drive circuit 132 so that the haptic drive signal cannot
damage components in the controller 162. Operating the sensor
switch 126 in this manner also prevents the input voltage,
V.sub.in, for the voltage divider 118 from providing a voltage
offset to the haptic drive signal. Such an offset may adversely
affect the haptic effect the controller 162 is trying to create
such as the sensation of certain levels of friction of the flow of
fluid.
[0042] In at least some exemplary embodiments, the controller 162
will cause the actuator drive circuit 132 to stop delivery of a
haptic drive signal and then switch the sensor switch 126 after a
determined period of time, returning the unitary haptic device 100
from the haptic-delivery mode back to the sensing mode. Other
embodiments may switch operation of the unitary haptic device 100
from the haptic-delivery mode to the sensing mode upon occurrence
of events other than the lapsing of a period of time.
[0043] In alternative embodiments, the sensor switch 126 can be a
mechanical switch, a semiconductor device, or any other suitable
switching mechanism. In other alternative embodiments, the sensor
switch 126 is replaced with two single pole, single throw switches,
with one switch connected in series between the actuator drive
circuit 132 and the first electrode 102 and the other switch
connected in series between the output voltage, V.sub.out, and the
first electrode 102. Other embodiments can have alternative types
and arrangements of switches to provide continuity to the first
electrode 102. Additionally, in lieu of the sensor switch 126 or
any other switches, the controller 162 can contain circuitry and
programming to control continuity to the first electrode 102 by
enabling and disabling outputs from the actuator drive circuit 132
and the input voltage, V.sub.in; by shielding the controller 162
from high voltages from the actuator drive circuit 132 that might
be received through the voltage divider 118; and by programming the
controller 162 to process and isolate voltages within aggregate
voltage signals.
[0044] Alternative embodiments use a piezoresistive cell as the
sensor element 106 in place of a quantum tunneling composite. A
piezoresistive cell is a metal or semiconductor material that has a
crystal lattice structure in which the crystals change shape and
direction under stress. These embodiments operate in substantially
the same way as described with reference to FIGS. 5A-5C, and the
piezoresistive cell changes resistance as it bends or compresses
and the crystal lattice structure is stressed. However, the
response of the voltage divider 118 is the opposite as it is when
the sensing element 106 is a quantum tunneling composite. The
resistance of the piezoresistive cell is low when it is unstressed
as illustrated in FIG. 5A, and thus the output voltage, V.sub.out,
at the node 124 is initially very low relative to the input
voltage, V.sub.in. As the sensor element 106 is placed under stress
as illustrated in FIG. 5B, resistance of the piezoresistive cell
increases and the output voltage, V.sub.out, at the node 124
increases in response to a user 116 touching the touch surface 112
of the unitary haptic device 100. The controller 162 reads the new
value of V.sub.out and determines whether it has risen above a
threshold level to cause the controller 162 to switch operation of
the unitary haptic device 100 from the sensor mode to the
haptic-delivery mode as shown in FIG. 5C. In embodiments that use a
piezoresistive cell as the sensor element 106, at least the
protective layer 110 and first electrode 102 bend as force is
exerted against the touch surface 112. The force then causes the
piezoresistive cell to bend or compress. Although in at least some
embodiments, the entire unitary haptic device 100, including the
protective layer 110, first electrode 102, sensor element 106, and
second electrode 104, is flexible or compressible.
[0045] Other alternative embodiments use a photoresistor as the
sensor element 106. A photoresistor is a semiconductor having a low
electrical resistance when exposed to light, but the resistance is
variable and increases as the amount of light reaching the
photoresistor falls. Accordingly, the output voltage, V.sub.out, at
the node 124 in the voltage divider 118 responds in substantially
the same way as embodiments using a piezoresistive cell as the
sensor element 106. In these embodiments, however, the resistance
of the photoresistor, and hence the output voltage at the node 124,
increases as a user's 116 finger approaches the touch surface 112
of the unitary haptic device 100 and blocks light from reaching the
sensor element 106. When the output voltage, V.sub.out, rises above
a threshold level indicating that a user 116 has touched the touch
surface 112, the controller 162 will switch operation of the
unitary haptic device 100 from the sensing mode to the
haptic-delivery mode. An alternative embodiment might set the
threshold value for the output voltage, V.sub.out, at a level
indicating the user's 116 finger is proximal to the touch surface
116, but not necessarily touching the touch surface 112. The
photoresistor is typically formed with a semiconductor material
such as silicon, germanium, or compounds of gallium. The
semiconductor material can be applied to the second electrode 104
using traditional fabrication techniques such as vapor deposition
or sputtering. Alternative embodiments can use other materials to
form the photoresistor.
[0046] In embodiments using a photoresistor as the sensor element
106, the controller 162 may be programmed to receive input from an
additional sensor measuring ambient light in the environment where
the unitary haptic device is operating. In these embodiments, the
controller 162 may then adjust the threshold value of the output
voltage, V.sub.out, according to the measured level of ambient
light such that the threshold value of the output voltage will be
lower if the ambient light is lower and the threshold value of the
output voltage will be higher if the ambient light is brighter.
Alternatively, the controller 162 can continuously monitor and
calculate a running average for the value of the output voltage,
V.sub.out, which would correspond to the amount of ambient light in
the environment where the unitary haptic device 100 is operating. A
higher average value of the output voltage would correspond to
brighter ambient light and a lower average value of the output
voltage would correspond to a lower level of ambient light. The
controller 162 can then use this running average of the output
voltage to adjust the threshold value for the output value at which
the controller 162 switches operation of the unitary haptic device
100 from the sensing mode to the haptic-delivery mode.
Additionally, because embodiments using a photoresistor rely on
sensing light and are not responsive to bending or compressing the
sensor element 106, the first electrode 102 and sensing element 106
can be rigid and non-compressible. Although in alternative
embodiments, the unitary haptic device 100 may be flexible or
compressible, or individual layers within the unitary haptic device
may be flexible or compressible. Additionally, in these
embodiments, at least the protective layer 110 and the first
electrode 102 have sufficient transparency to let ambient light
pass to the sensor element 106. An advantage of these embodiments
is that a system can be programed to deliver haptic effects when a
user's 116 finger or another pointer is proximal to, but not
touching, the touch surface 112.
[0047] FIGS. 6A and 6B illustrate an embodiment of the unitary
haptic device 100 configured to simultaneously sense touch and
deliver a haptic effect using ESF or TES. In this embodiment, the
actuator drive circuit 132 is in electrical communication with the
second electrode 104. As illustrated, this embodiment uses a sensor
element 106 having a material that has increasing conductance and
decreasing resistance as it is compressed such as quantum tunneling
composites as disclosed herein or a similar material. When the
sensor element 106 reaches a certain level of compression it
realizes a sufficiently high conductivity that results in minimal
attenuation of a signal applied to the second electrode 104.
[0048] In operation, with reference to FIG. 6A, when a user is not
touching or exerting a force against the touch surface 112 of the
unitary haptic device 100, the sensor element 106 is not stimulated
and provides a high electrical resistance so only a small current
flows from the second electrode 104 and the first electrode 102.
The amplitude of the haptic drive signal that flows through the
sensor element 106 to the first electrode 102 is so low that a user
cannot sense any stimulation and a haptic effect cannot be
delivered to a user 116. In an alternative embodiment, the quantum
tunneling composite in the sensor element 106 provides an open
circuit and electrically isolates the first electrode 102 from the
second electrode 104 and the actuator drive circuit 132.
[0049] As illustrated in FIG. 6B, however, as the user 116 exerts
pressure against the touch surface 112, the sensor element 106 is
compressed and the conductivity increases and the amplitude of the
haptic drive signal flowing from the second electrode 104 to the
first electrode 102 increases. When conductivity of the quantum
tunneling composite reaches a high enough level, the amplitude of
the actuator drive signal reaching the first electrode 102 becomes
high enough to generate a potential between the first electrode 102
and the user's 116 skin that is sufficient to generate an ESF and
deliver a haptic effect, or high enough to conduct a current
through the first electrode 102 and the protective layer 110 that
is sufficient to deliver TES and deliver a haptic effect. An
advantage of the embodiment illustrated in FIGS. 6A and 6B is that
it continuously monitors pressure exerted against the unitary
haptic device 100. In at least some embodiments, as pressure
changes the amplitude of the haptic drive signal that is conducted
from the second electrode 104 to the first electrode 102 changes,
which can change the strength of the haptic effect.
[0050] Alternative embodiments of the unitary haptic device 100
that simultaneously sense touch and deliver haptic effects are
possible. For example, the unitary haptic device 100 can use any
suitable sensor elements other than quantum tunneling composites
that pass the haptic drive signal from the second electrode 104 to
the first electrode 102 with minimal attenuation so that the signal
has sufficient amplitude or current to deliver an ESF or TES,
respectively. Additionally, alternative embodiments might use
haptic actuators other than a single electrode (e.g., first
electrode 102) for delivering an ESF or TES. Examples of
alternative actuators include piezoelectric cells, smart materials
such as electroactive polymers, microfiber composites, shape memory
polymers and metals, and any other material that vibrates or
changes shape upon receiving external stimulation such as an
electrical potential, electrical current, electrical field,
magnetic field, or temperature change.
[0051] FIG. 7 illustrates an alternative embodiment of a unitary
haptic device. In this alternative embodiment, a unitary haptic
device 136 includes a first electrode 138, second electrode 140,
and third electrode 142. A protective layer 144 is substantially
similar to the protective layer 110 and covers the first electrode
138. The protective layer 144 has a touch surface 148. An
electrical insulator 146 is positioned between and isolates the
first and second electrodes 138 and 140. A sensor element 150 is
positioned between the second electrode 140 and the third electrode
142. As discussed herein, for unitary haptic devices 136 that
deliver haptic effects using ESF, the protective layer 144 is an
insulator formed with a dielectric material. The sensor element 150
is substantially similar to the sensor element 106 discussed herein
and detects touch or, in some embodiments, proximity to the touch
surface 148. Examples of sensor elements 150 that detect touch
include quantum tunneling composites, piezoresistive cells,
photoresistors, and other materials that change electrical
properties such as conductivity or capacitance when exposed to or
deprived of an external stimulation or force such as pressure or
light. Photoresistors also are able to detect proximity. If the
sensor element 150 is a photoresistor, at least the protective
layer 144, first and second electrodes 138 and 140, and electrical
insulator 146 are substantially transparent so ambient light can
reach the sensor element 150 and stimulate the photoresistor so
that is has minimal electrical resistance. The unitary haptic
device 136 can have flexibility and transparency characteristics
similar to unitary haptic device 100.
[0052] When implemented, the unitary haptic device 136 illustrated
in FIG. 7 operates similar to the embodiments illustrated in FIGS.
5A-5C. A voltage divider 152 is formed with a first resistance or
impedance 154 that is in series with a node 156. A second
resistance or impedance is provided by the sensor element 150,
which is in electrical series between the resistor 154 and ground
158 through the third electrode 142 and second electrode 140. An
output voltage, V.sub.out, is output at the node 156. The voltage
divider 152 forms a sensor circuit. Additionally, the first
electrode 138 is electrically connected to the actuator drive
circuit 132. As the output voltage, V.sub.out, from the voltage
divider changes and moves past a threshold value, the controller
162 will determine that a haptic effect should be delivered to a
user 116 and control the actuator drive circuit to deliver a haptic
signal to the first electrode 138.
[0053] An advantage of this embodiment is that it simultaneously
monitors the user's 116 interaction with the unitary haptic device
136 and delivers a haptic effect. The controller 162 can be
programmed to continuously monitor the output voltage, V.sub.out.
As the force the user 116 exerts against the unitary haptic device
136 changes, the output voltage, V.sub.out, at the node 156 also
changes. The controller 162 can be programmed to sense the output
voltage, V.sub.out, and then modify one or more electrical
characteristics of the haptic drive signal in real-time with
respect to sensing a change in the output voltage while continuing
to monitor the output voltage, although there may be at least some
delay between sensing a change in the output voltage and changing a
characteristic of the haptic drive signal due to latency in
performance of the sensors, processing speeds of the processors,
and other factors. Another advantage of this embodiment is that the
electronics interfacing the unitary haptic device 136 with the
controller 162 do not need switching and are less complex, less
prone to failure, require less power, and have smaller packaging
requirements. Additionally, programming the controller 162 is
simpler at least because the controller 162 does not need to switch
the unitary haptic device 136 between sensing and haptic modes and
does not need to enable and disable sensing and haptic delivery
circuits.
[0054] FIG. 8 illustrates an embodiment of a segmented user
interface 160 using a plurality of unitary haptic devices 100 or
136. The unitary haptic devices 100 or 136 can be arranged randomly
or in any pattern. The illustrated embodiment is a 3.times.3 array
of unitary haptic devices 100 or 136, although alternative
embodiments can use more or fewer unitary haptic devices 100 or
136. Other embodiments can arrange the unitary haptic devices 100
or 136 in different patterns such as circles, ovals, rectangles,
squares, triangles, or any other shape or geometric arrangement.
Additionally, embodiment might include two separate groups of
unitary haptic devices 100 or 136, with each group positioned in a
separate portion of a user interface. The user interface can be a
display, touch pad, or any other surface with which a user
interacts. In these embodiments, each of the unitary haptic devices
100 or 136 in the segmented user interface 160 can be controlled by
separate and individual sensing circuits and haptic delivery
circuits. Accordingly, each unitary haptic device 100 or 136 can be
controlled individually, and can be controlled to deliver a
different haptic effect and to respond to different pressures. For
example, one unitary haptic device 100 or 136 can be controlled to
deliver a haptic effect upon sensing a first pressure and a
different unitary haptic device 100 or 136 can be controlled to
deliver a haptic effect upon sensing a second, different
pressure.
[0055] Referring now to FIG. 9, a controller 162 for the unitary
haptic devices 100 or 136 includes a bus 168, a processor 170, an
input/output (I/O) controller 172 and a memory 174. The bus 168
couples the various components of the controller 162, including the
I/O controller 172 and memory 174, to the processor 170. The bus
168 typically comprises a control bus, address bus, and data bus.
However, the bus 168 can be any bus or combination of busses
suitable to transfer data between components in the controller 162.
The controller 162 also may interface with a switching circuit 166
for controlling the sensor switch 126.
[0056] The processor 170 can comprise any circuit configured to
process information and can include any suitable analog or digital
circuit. The processor 170 can also include a programmable circuit
that executes instructions. Examples of programmable circuits
include microprocessors, microcontrollers, application specific
integrated circuits (ASICs), programmable gate arrays (PGAs), field
programmable gate arrays (FPGAs), or any other processor or
hardware suitable for executing instructions. In the various
embodiments, the processor 170 can comprise a single unit, or a
combination of two or more units, with the units physically located
in a single controller or in separate devices.
[0057] The I/O controller 172 comprises circuitry that monitors the
operation of the controller 162 and peripheral or external devices.
As disclosed herein, the output voltage, V.sub.out, from the nodes
124 or 156 is input to the I/O controller 172, which then
communicates this value to the processor 170 for processing. The
I/O controller 172 also manages data flow between the controller
162 and peripherals or external devices (not shown). The external
devices can reside in the same device in which the controller 162
and unitary haptic devices 100 or 136 are incorporated or can be
external to the system. Examples of other peripheral or external
devices with which the I/O controller 172 can interface include
sensors, external storage devices, monitors, input devices such as
keyboards, mice or pushbuttons, external computing devices, mobile
devices, transmitters/receivers, and antennas.
[0058] The memory 174 can comprise volatile memory such as random
access memory (RAM), read only memory (ROM), electrically erasable
programmable read only memory (EEPROM), flash memory, magnetic
memory, optical memory or any other suitable memory technology. The
memory 308 can also comprise a combination of volatile and
nonvolatile memory.
[0059] The memory 174 is configured to store a number of program
modules for execution by the processor 170, including a sensor
monitor module 176, a haptic effect determination module 178, and a
haptic effect control module 180. Each program module is a
collection of data, routines, objects, calls and other instructions
that perform one or more particular task. Although certain program
modules are disclosed herein, the various instructions and tasks
described for each module can, in various embodiments, be performed
by a single program module, a different combination of modules,
modules other than those disclosed herein, or modules executed by
remote devices that are in communication with the controller
162.
[0060] In an example embodiment, the sensor monitor module 176
monitors the output voltage, V.sub.out, output at the node 124 or
156 and determines when a haptic effect should be delivered to a
user 116. An example technique that the sensor monitor module 176
can use to determine whether to deliver a haptic effect includes a
comparator or a pointer. The sensor monitor module 176 would
monitor the output voltage, V.sub.out, at the node 124 or 156 and
compare it to a determined value, and determine a haptic effect
should be delivered when the output voltage is less than the
determined or threshold value (if the sensor element is a quantum
tunneling composite) or greater than the determined or threshold
value (if the sensor element is a piezoresistor or photoresistor).
In another embodiment, the sensor monitor module 176 uses
alternative calculations to process the output voltage, V.sub.out,
to determine whether to deliver a haptic effect. In yet another
embodiment, the sensor monitor module 176 references the output
voltage, V.sub.out, to a lookup table to determine whether to
deliver a haptic effect.
[0061] In an example embodiment, the haptic effect determination
module 178 determines which haptic effect to deliver through the
unitary haptic device 100 or 136. An example technique that the
determination module 178 can use to determine which haptic effect
to deliver includes rules programmed to make decisions to select a
haptic effect. For example, the controller 162 may interface with
GPS receiver or other location tracking device and determine
different haptic effects that should be delivered based on the
user's location and whether they are moving. In another example,
the controller 162 may determine the haptic effect that should be
delivered based on an application being executed by an electronic
device, a particular event that occurred when executing an
application, or data that was received from an external sensor or
third party device.
[0062] In an alternative embodiment, a lookup table references
values for the output voltage. V.sub.out, to different haptic
effects. The haptic effect determination module 178 then references
the output voltage, V.sub.out, to the lookup table to determine
which haptic effect to deliver. For embodiments utilizing unitary
haptic device 136 and implementations that simultaneously monitor
contact and deliver haptic effects as illustrated in FIG. 7, the
haptic effect determination module 178 can continuously compare the
output voltage, V.sub.out, to the lookup table and modify the
haptic effect that is delivered to the user 116 as pressure or
contact applied against the unitary haptic device 136 changes.
[0063] Upon the haptic effect determination module 178 determining
which haptic signal to deliver to the unitary haptic device 100 or
136, it communicates that determination to the haptic effect
control module 180. For embodiments that utilize the unitary haptic
device 100, the haptic effect control module 180 then communicates
a command to the switching circuit 166 to control the sensor switch
126 to open thereby changing the unitary haptic device 100 from the
sensing mode to the haptic-delivery mode. For embodiments that
utilize the unitary haptic device 136, which simultaneous senses
touch and delivers haptic effects, the haptic effect control module
180 may not generate a switching command.
[0064] Additionally, the haptic effect control module 180 obtains
the electrical parameters or characteristics that correspond to the
determined haptic effect. The haptic effect control module 180
communicates the electrical parameters to the I/O controller 172,
which then generates a haptic signal embodying the electrical
parameters provided by the haptic effect control module 180. The
I/O controller 172 communicates the haptic signal to the actuator
drive circuit 132, which generates an alternating waveform and
amplifies the waveform to generate the haptic drive signal. The
actuator drive circuit 132 applies the haptic drive signal to the
first electrode 102 or 138 in the unitary haptic device 100 or 136,
respectively. The I/O controller 172 and the actuator drive circuit
132 may perform additional processing to the haptic signal and
haptic drive signal.
[0065] Examples of signal parameters that can be used to generate
the haptic signal include frequency, amplitude, phase, inversion,
duration, waveform, attack time, rise time, fade time, and lag or
lead time relative to an event. Additionally, although the actuator
drive circuit 132 is disclosed as having a signal generator,
alternative embodiments may output a signal that is not
alternating. Examples of signals and waveforms for the haptic
signal and the haptic drive signal include direct current signals,
alternating current signals, alternating voltage signals, square
waves, sinusoidal waves, step signals, triangle waves, sawtooth
waves, and pulses.
[0066] In an alternative embodiment, there is no determination of
the haptic effect to be delivered through the unitary haptic device
100 or 136 or the electrical parameters to use for generating the
haptic drive signal. In such an embodiment, the controller 162 is
simply programed, or even hard wired, to deliver a determined
haptic drive signal to the unitary haptic device 100 or 136.
[0067] The unitary haptic devices 100 and 136, and alternative
embodiments thereof, can be used in a variety of applications.
Examples include computing devices such as desktop computers,
laptops, tablets, smartphones and other cellular phones; wearable
devices such as smartphones; gaming devices such as consoles and
controllers; vehicles; machinery; medical devices such as surgical
equipment, catheters, monitors, orthoscopic devices, surgical
simulators, surgical robots; instrumentation; keypads; robot
controllers, and any other thing having electronics and a user
interface. Additionally, the unitary haptic device 100 and 136, and
alternative embodiments thereof, can be used in conjunction with
touchpads; touch displays, including capacitive touch displays, and
other user interfaces. Additionally, when used on displays and
similar interfaces, the unitary haptic device 100 and 136 are
substantially transparent and form a layer of the display or other
interface.
[0068] The various embodiments described above are provided by way
of illustration only and should not be construed to limit the
claims attached hereto. Those skilled in the art will readily
recognize various modifications and changes that may be made
without following the example embodiments and applications
illustrated and described herein, and without departing from the
true spirit and scope of the following claims.
* * * * *