Phono-Luminous Paper

Touch responsive electroluminescent loudspeaker

27 Oktober 2016

Phono-Luminous Paper is a novel material, which produces both light and sound in response to touch. By gently touching the surface of the material, traces of light emerge and the surface itself resonates with a modulating tone. This material was produced in as a part of a series of experimental demonstrations exploring the topic of light and ephemeral materials at Enactive Environments Lab of Zurich University of the Arts.

Paper acts both as a sensor and a sounding device

Unlike any other audio-visual touch display, Phono-Luminous Paper is a completely analogue technology. No computer is present anywhere in the construction. The unique combination of technologies allows this material to act both as a sensor, a display, and a sounding device. In this sense, the interactive capabilities are programmed during the material fabrication and the computation happens inside the the material itself. It serves as a demonstration of the computational qualities, and interactive capabilities of emerging material technologies.

The material is fabricated by screen printing a combination of electrically active layers onto paper stock, which is combined with a protective sheet of polyester film. This fabrication method allows for cost effective mass production and scalability. The flexible nature allows it to be integrated in many different surfaces and forms. Further to this, the device consumes very little power, making it possible to construct not only small devices, but entire walls or spaces from the material.

image: Phono-Luminous Paper run by fluid

The phenomena of light and sound are produced by the combination of electroluminescence and electroacoustic transduction, which are both driven by an alternating current power supply. The material, together with the induction coils in the AC power supply, form a resonant circuit which modulates in response to pressing the the material. The resulting frequency resonates in the material to produce a tone between 340 and 810 Hz.

Other experiments also include devices such as “Liquid Light” where water was used in the construction of an Electroluminescent display. Here the light is produced in interaction with the ebbing and flowing of a stream of water over the films surface.

The source of the light is in the same alternating current that produces the sound. Through a remarkable concurrence of nature, a phosphor of copper-zinc-sulfide will produce light when exposed to the same frequencies of electrical charge as the audible tone. Through the process of electroluminescence, phosphors integrated into the material begin to emit light in response to this high frequency alternating current. The light can range from cool green to blue colour temperatures. Additional colours are also possible with additives during the fabrication process. This conversion from power into visible light occurs with a high degree of efficiency.

images: Luke Franzke