angry tapir writes "Using infrared sensors like the ones on television remote controls, Texas A&M University students presented an inexpensive multitouch system at the Computer Human Interaction (CHI) conference in Vancouver. "I like to consider it an optical force field; it's like a picture frame where we shoot thousands of light beams across and we can detect anything that intersects that frame," said Jonathan Moeller, a research assistant in the Interface Ecology Lab at Texas A&M University. The frame is lined with 256 IR sensors, which are connected to a computer. When ZeroTouch is mounted over a traditional computer screen it turns the display into a multitouch surface. Taken one step further, if the screen is suspended then a user could paint a virtual canvas. (Pics and video in link.)"
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