Tech - Pinch-screen puts all your fingers in control

PICK up a tablet computer or smartphone and you may find you naturally cradle it in your hands, with both thumbs poised to tap away at the touchscreen. Banging out emails or navigating a music library this way may seem like a breeze, but what if we could bring our other eight digits in on the act?

Katrin Wolf of the Deutsche Telekom Laboratories at the Technical University of Berlin, Germany, has done just that. She has built a device that exploits our thumbs' natural ability to line up with our fingers even when we can't see them - a talent known as proprioception.

Wolf attached two iPads back-to-back to create what she calls a PinchPad. It can sense when a user's fingers and thumbs make a pinching motion with the two tablets sandwiched in between.

For example, touching your thumb to your index finger on opposite sides of the PinchPad can be interpreted as a "select" or "undo" command, while sweeping the thumb from one finger to the next could adjust volume or brightness, Wolf says. And moving the thumb in little circles over each finger can let you manipulate on-screen dials. Wolf will present her work next month at the TEI conference in Kingston, Ontario, Canada.

This is not the first device with a touch-sensitive back, says Chris Harrison at Carnegie Mellon University in Pittsburgh, Pennsylvania. Microsoft once built a prototype device called Nano Touch with this feature, and the next version of Sony's handheld PlayStation console, the Vita, will have it too. Harrison says Wolf's work is useful because of the novel gestures it offers. "And you get extra buttons for free without having to put anything on screen," he says.

http://www.newscientist.com/