iO Personal Digital Pen

Bill Buxton's Notes

This system uses technology developed by a Swedish company, Anoto, to capture what is written with ink on paper. To avoid the problems of the CrossPad, special paper with embedded glyphs is required. These glyphs are near invisible to the human eye, but they encode their own location on the page, as well as the page itself, and do so in a way that can be seen by a miniature camera embedded in the stylus. Hence, registration between the physical and digital ink is pretty much ensured. The only real penalties are the need for special paper and for a pen that is fatter than one would use otherwise.