le jour ou t'auras bien compris qqch avant de dire n'importe quoi ...

Those cameras, which are located below the acrylic surface of the table, can read a nearly infinite number of simultaneous touches, and are limited only by processing power. Keam says that Surface has been optimized for 52 touches—enough for four people to use all 10 fingers at once and still have 12 objects sitting on the table.

http://arstechnica.com/news.ars/post/20070530-what-lurks-below-microsofts-surface-a-qa-with-microsoft.html