August 24, 2007
Multi-touch Display Uses All Ten Fingers
By Stuart J. Johnston
Multi-touch screen technologies are the latest thing for high-tech gadgets, from Apple's iPhone to Microsoft's Surface tabletop computer.
to date, there has been a limit to how useful a multi-touch interface
could be. It's not practical in most circumstances, for instance, to
put all ten fingers on a touch screen at once. For one thing, since the
screen is there to display information, putting all of your fingers on
the screen blocks the view of the information.
a joint project between Microsoft Research (MSR) and Mitsubishi
Electric Research Labs (MERL) has resulted in a novel solution – touch
screens on both the front and back of a mobile device that are used
simultaneously. The user's thumbs touch the front screen while the
other eight fingers touch the back on what's been termed the LucidTouch "see through" mobile device interface.
be precise, the device's screen is not actually transparent. Instead, a
camera on a short boom attached to the prototype's back captures images
of the user's hands touching the rear screen, and an image of the
fingers – to enable the user to "see" where his or her fingers are
touching – is displayed on the front screen as if the device was
the thumbs on the front screen and fingers touching the back, for
example, users are able to type more easily – using a slightly
reoriented QWERTY keyboard layout -- than on other touch screen
interfaces. The fact that users can have multiple fingers on the screen
at once, without blocking (or "occluding") the view also enables easier
use of maps, for instance.
actually making the device transparent front to back was too
problematic, according to MSR research scientist Patrick Baudisch.
That's why the researchers adopted the term "pseudo-transparent" – the
transparency is actually an intentional optical illusion.
hard to get the illumination right [if it were actually transparent
and] … we can stick with a regular design with the electronics in the
middle of the device [instead of having to position the chips and
motherboard around the edges]," Baudisch told internetnews.com.
not showing the fingers was confusing to users, so the researchers
figured out a way – using a camera at this point but later probably
surface-based sensors – to show the finger locations, as if the
device's screen was actually transparent.
The current prototype uses a form factor that is similar in size to Microsoft's "ultra-mobile PC" or UMPC
design. However, the researchers continue to experiment and are looking
at other form factors, such as personal digital assistants (PDA) and
tablet PC devices.
Baudisch is quick to point out that the project is a true collaborative
effort with Mitsubishi researchers, including MERL's Daniel Wigdor.
"Daniel did a lot of the engineering," Baudisch added.
researchers plan to publish a paper in early October when they present
their work at the Association for Computing Machinery's (ACM) Symposium
on User Interface Software and Technology.
the work is not, as such, a product design – rather it is a research
project – Microsoft's recently introduced Surface computer began in a
somewhat similar manner, as an outgrowth of an MSR research project. So
it is not outside the realm of possibilities that follow-on research
might yield usable technologies at some future point in time.
In the meantime, however, don't look for devices with the LucidTouch technology on the shelves at Best Buy any time soon.
"This is all just starting," Baudisch said.