Part of the show Surround sound stereo with only one speaker
Interaction expert Joe Paradiso from Massachussets Institute of Technology (MIT) Media Lab says that he can turn a shop window into an interactive 'touch screen'. This would allow shoppers to, for example, trigger demonstrations in the window, rotate displays, or pick things from a menu. This can be done, he says, simply by placing microphones in each corner of the window. When a shopper taps on the glass, the time it takes the vibrations to reach each of the microphones in turn can be used to pinpoint where on the glass a person is tapping. A computer can work out which 'button' on the glass the person wants to activate, and so change the display accordingly.