Because the system can trace the movement of fingers on any surface, it can be set up to recognize gestures such as pinch-zooming on a map.

Microsoft Research Redmond researcher Hrvoje Benko said in a statement: "We wanted the ability to use any surface.

"Let the user define the area where they want the interface to be, and have the system do its best to track it frame to frame. This creates a highly flexible, on-demand user interface."

Photo: Microsoft Research/CMU