A Revolution in Touch
Dave Gillespie
R&D Fellow
Synaptics, Inc.
Synaptics and touch sensing
• Synaptics, Inc was founded in 1986 by Carver Mead and
Federico Faggin
• www.synaptics.com
• Original mission: Find commercial applications for neural
networks embedded in analog VLSI chips
• I came to Synaptics from Carver’s lab at Caltech in 1991
• The analog NN market never materialized, but two side
projects at Synaptics took on a life of their own:
• One was Carver’s imaging chips, which spun off to Foveon
• The other was capacitive touch sensors
• Synaptics’ bread and butter today is capacitive input devices
such as TouchPads for laptops and, now, MP3 players, etc.
• What is it about touch sensors that is so compelling?
• What led to their success? Where do we go from here?
© 2004 Synaptics Confidential
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Interacting through touch
• Machines of all kinds have always been controlled by an
operator’s touch
• Through buttons, switches, knobs, dials, levers, handles
Humblest machines
Earliest machines and tools
Largest machines
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Simple control paradigms work well for simple
machines
… but they are stretched as machines grow in complexity
… and can be stretched too far
Example: Plugging and unplugging
Telephone switchboard
First electronic digital computer
ENIAC, 1946
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Touch control is a kind of communication
• The more a machine is able to do, the richer must be the
“language” we use to tell it what to do
• A control must be expressive enough to fit the “language”
it communicates
• “Plugged / unplugged” is a language of just two words – great for
a table lamp, but a clumsy way to express a computer program
“On or off?”
A perfect match
© 2004 Synaptics Confidential
“Which connection?”
Barely manageable
“What computation?”
Overwhelming!
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As machines have grown more capable, their
input devices have grown more expressive
• This evolution has been especially easy to see in computers
• Computers have grown in complexity by leaps and bounds
during our lifetime
• Instead of controlling a computer, we converse with it
• Today’s input devices must be able to express a rich
conversational language of actions and information
Arrow keys
Handwriting
Direct connection
Mouse
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The Synaptics TouchPad
• We developed the TouchPad to meet a simple need
• Portable computers needed a flat alternative to the mouse
• Federico Faggin was on the BOD of Logitech, who supplied
trackballs to the first generation of laptops
• But we have found that the greater expressiveness of the
TouchPad takes it a step beyond the mouse
• Handwriting entry is one example
• Signature capture – pen TouchPad
• Synaptics’ Virtual Scrolling feature
presaged mouse scrolling wheels
• Research continues in these areas
• But the real excitement and opportunity
for touch input devices lies beyond
conventional personal computers
© 2004 Synaptics Confidential
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Remember this ad campaign?
• Applied Materials, “Information for Everyone”
• The message: Computers today are all around us, underlying
the function of even the most commonplace objects
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A revolution with big ramifications for touch input!
• As objects become computers, the character of our
interaction with them changes fundamentally
• These devices are no longer simple tools we turn on and off
• They become intelligent partners in a conversation with us
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Intelligent devices
• Devices that once were very simple …
… now have microprocessors and a rich user interaction
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Intelligent devices and touch
• One thing these devices all have in common with their
forebears:
• Each one is still operated by a person’s touch
• But the kind of touch control is far richer than before
• From a ten-position phone dial to a fold-out full text keyboard
• From “play” and “rewind” buttons to a nuanced scroll wheel
• From “toast it now” to a detailed electronic control panel!
• From a passive object to an active participant in a child’s play
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For many intelligent devices today, buttons are
becoming as “quaint” as the ENIAC’s plug board
• Fitting a 50+ key text keyboard onto a phone is a nifty feat of
design, but there must be a better way!
• It is hard to navigate among thousands of MP3 tracks using
just a few buttons
• With its handful of microswitches, Furby couldn’t tell whether
it was being hugged, petted, drop kicked, or tickled
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A new generation of touch sensors
• New touch sensors provide the expressiveness that
modern intelligent devices require
• Capacitive touch sensors are a good example
• Such as Synaptics’ TouchPad™, ScrollStrip™, ScrollDisc™
• These sensors detect touch by measuring how the finger
affects the electric field around it
• This is the electrical phenomenon of “capacitance”
Columns
Rows
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Capacitive touch sensors are superbly expressive
• They sense close proximity as well as direct touch
• They can locate the finger to within 1/1000 of an inch
• They can sense smooth motion and gestures
• They can find the finger’s absolute location on the sensor
• They can measure the area of contact and finger pressure
• They can detect multi-finger touch
HELLO
Data
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Expression
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Capacitive touch sensors are suited to many
diverse applications
• They are inexpensive and completely solid-state
• They can be made in a variety of forms: Flexible, big,
small, very thin, transparent, under thick plastic (or fur?)
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A revolution in touch
• At Synaptics, we have found that the capacitive technology
we developed for the laptop TouchPad is perfect for
countless other applications
• Today: MP3 players, phones, PDAs
• In the future: Appliances? Toys? Cars? Light switches?
Remote controls?
• As the devices all around us become intelligent devices,
revolutionary touch sensing technologies will be there to
meet their needs for a rich human interface
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