Light-emitting diodes (LEDs) have long been considered the technology of the future in the lighting industry. Scientists at the Heinrich Hertz Institute of the Fraunhofer Institute for Telecommunications (HHI) in Berlin are now working on another rather remarkable possible application for these high-tech lamps: they want to use the modern light sources to transmit data and information while lighting a room.
© Fraunhofer HHIThis would make it possible, for example, to transmit films or other video material quickly and securely to a laptop or a mobile phone - directly from the LED in the lamp in the living room ceiling. This form of transmission is made possible by a wireless optical data transfer system, which is known as optical WLAN for short. The new technology, which Fraunhofer researchers in Dr. Anagnostis Paraskevopoulos's team call Visible Light Communication (VLC), does not need a great deal of equipment to work: a powerful, commercially available LED serves as the transmitter.
The researchers have developed an additional component in cooperation with Siemens experts to be able to transmit data. This so-called modulator is connected to the electricity circuit before the LED lamp - and in effect switches it on and off extremely fast. All you need as a receiver is a simple photodiode, for example, on a laptop computer. It captures the light, electronics decode the information and then translate it into electrical impulses, which is the language understood by the computer.
The researchers believe that optical data transfer using VLC is an interesting alternative to known radio-based wireless network technology or glass-fibre cables - without the need for new wiring or equipment inside a building. VLC could also be used in hospitals. In operating theatres, for example, where a conventional wireless network would interfere with medical equipment, some of the communication could be run through the operating lamp to control surgical robots or transmit X-ray images.
Fraunhofer Heinrich Hertz Institute
26. October 2016
University of Twente
13. October 2016
Magdeburg-Stendal University of Applied Sciences
25. November 2016
University of Freiburg