We just finished our multi-touch and RFID setup. The idea is a segmented multi-touch display. The screen is segmented into multiple areas each of which has its own antenna. The antenna is below the plexiglas and made of 0.1mm wire. This is roughly 8 times more then the horizontal dampening wire found in Trinitron screens. As a side note, the 0.1mm is not a physical minimum but rather a realization/sanity reason. In theory the wire for the antenna could be even smaller.
Unfortunately the only reasonably priced plexiglas we could find was a 20*30cm which made it unrealistic to use rear-projection on it. And also very hard to put the antenna into it. It was also not very helpful that we only had 3 weeks for realization A more detailed description will follow later.
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