This is from an article on BBC back in 2007: “Researchers from Mid Sweden University have constructed an interactive paper billboard that emits recorded sound in response to a user’s touch. The prototype display uses conductive inks, which are sensitive to pressure, and printed speakers.
The key to the billboard’s capabilities is a layer of digital paper that is embedded with electronics. This is printed with conductive inks, which, when applied with pressure, relay information to a…
