The researchers at Disney Research, Pittsburgh, used electrets, materials with special electrical properties that are already used in microphones and in tiny MEMS devices to develop this latest application.
This new approach could make possible new types of interactive applications involving books, posters and other printed materials that require no batteries or external power.
The design of a Paper Generator is simple: one approach is to sandwich a thin, flexible sheet of polytetrafluoroethylene, or PTFE - best known by the brand name Teflon -between two conductive layers, such as sheets of metallized polyester, that serve as electrodes.
Electrical charge accumulates on the PTFE sheet when paper is rubbed against it. Then, if the electrodes are made to move relative to each other against the PTFE, a tiny, alternating electrical current is generated. This electrical current can be used to power a broad variety of devices such as LED arrays, e-ink displays, sound buzzers and infrared communication devices.
"Though the fundamental principles of operation remain the same, it's possible to build Paper Generators that respond to a number of different gestures, such as tapping, touching, rubbing or sliding," Ivan Poupyrev, director of Disney Research, Pittsburgh's Interaction Group said.
The Paper Generators produced at Disney Research, Pittsburgh, by contrast, are decidedly low-tech and cheap.
Researchers demonstrated devices, which included a cartoon of a rocket ship outlined by a string of LEDs that light up when a paper button is tapped. The researchers also printed Paper Generators using conventional ink-jet printers equipped with cartridges with conductive ink.
Though the current produced by the devices is low - measured in hundreds of microamperes - the voltage is high, up to 1000 volts. That is ideal for triggering e-paper displays, Karagozler said.
The study will be presented at the ACM Symposium on User Interface Software and Technology in St Andrews, Scotland.
--ANI (Posted on 08-10-2013)