Researchers at Disney have developed a technology that can generate enough energy from the movement of a fingertip to light a string of LEDs or to control lights or other electrical components on e-paper or printed materials.
The Paper Generator -- developed primarily by Disney Research scientists in Pittsburgh -- relies on the placement of a sheet of polytetrafluoroethylene (PTFE), more commonly known as Teflon, between two thin reactive layers of material like metalized polyester that act as electrodes. Researchers Mustafa Emre Karagozler, Ivan Poupyrev, Gary Fedder, and Yuri Suzuki describe the new technology in this paper. It seems like an energy-harvesting version of touch technologies used in mobile devices. The user rubs, taps, or slides a finger over the materials to generate electricity.
The Paper Generator harvests energy when the user rubs, taps, or slides a finger over a thin sheet of Teflon sandwiched between two thin sheets of reactive material. Invented by researchers at Disney Research, the technology could be used to power small devices or interactive technologies for e-games or displays.
(Source: Disney Research)
A key component of the technology is the leveraging of electrets (materials with electrical properties) already used in microphones and MEMS devices. When the reactive paper layer rubs against the Teflon sheet, an electrical charge accumulates. If the electrons move relative to one another against the Teflon -- the action caused by the rubbing or sliding -- it generates a small current that can power a number of devices, the researchers wrote in their paper.
The operation of the Paper Generators relies on the movement of the two conductive sheets relative to each other and the electric field source, i.e., PTFE. As the relative positions of the sheets change, the distribution of the induced charges, the electric field, and the total capacitance between the sheets change, resulting in an electric potential difference between the conductors... Hence, the mechanical movements of the sheets and the field source are converted into electrical potential energy that can do work.
Poupyrev, director of the Pittsburgh interaction group for Disney Research, told us in an email that the Paper Generator can eliminate the need for power sources for some small devices, such as infrared communication devices or LED displays. This would make it easier for designers to add visual and audio technology to printed and e-paper materials. "We can imagine any number of ways to use this to add sights, sounds, and other interactivity to books and other printed materials inexpensively and without having to worry about power sources."
He would not discuss how Disney will employ the technology.