Humans have been using paper for more than 2000 years. Naturally, some improvements have been made along the way. Now scientists have figured out how to make paper touch-sensitive.
Researchers at Carnegie Mellon started with ordinary paper — the same sort you would find in the tray of any copier or printer. To impart touch capabilities, they applied a conductive coating to the paper.
It’s not simply an all-over coating, mind you. The paper has traces that connect 16 different points spaced evenly around the sheet back to the top-right corner. You can think of it like a USB port.
A clip gets attached to that point, and it’s wired to a sensor board that pumps current into the paper and watches for voltage drops caused by a touch. Tracking is fast and accurate at around 35 FPS.
You can use your finger just like you would on any capacitive touchscreen. Tools that you’d normally use on a piece of paper will work just fine, too. Pens, pencils, and even brushes… as long as it’s conductive you’re good to go.
Some minor modifications might be required depending on what you’re using. The graphite in a pencil is conductive, for example, but not the wood exterior. The CMU team overcame that by applying a bit of foil tape.
How much does it cost to turn paper into a touch-sensitive input device? For their experiments, the Carnegie Mellon researchers say it ran about 30 cents per page, which isn’t too bad… though it’s about three times what you’d pay for a single sheet of LiveScribe’s dot paper. Admittedly that’s a bit of an apples/oranges comparison, since LiveScribe (and other similar systems) utilize high-tech pens.
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