Research project taps LED lighting for broadband communications

January 25, 2013 // By Christoph Hammerschmidt
Tiny LED lights now being developed could deliver Wi-Fi-like internet communications, while simultaneously displaying information, a group of British scientists hopes. The technology in question will at the same time provide illumination for homes, offices and a whole host of other locations.

Over the next four years, with Engineering and Physical Sciences Research Council (EPSRC) funding, a consortium of UK universities led by the University of Strathclyde will be developing this innovative technology to help unleash the full potential of 'Li-Fi' – the transmission of internet communications using visible light rather than the radio waves and microwaves currently in use.

Although the potential possibilities offered by Li-Fi are already being explored all over the world, the EPSRC-funded consortium is pursuing a distinctive vision that could deliver enormous benefits, the scientists promise: Underpinning Li-Fi is the use of light emitting diodes (LEDs), a rapidly spreading lighting technology which is expected to become dominant over the next 20 years. Imperceptibly, LEDs flicker on and off thousands of times a second. By altering the length of the flickers, it is possible to send digital information to specially adapted PCs and other electronic devices – making Li-Fi the digital equivalent of Morse Code. This would make the visible part of the electromagnetic spectrum available for internet communications, easing pressure on the increasingly crowded parts now used.

But rather than developing Li-Fi LEDs around 1mm 2 in size, which other researchers around the world are concentrating on, the EPSRC-funded team is developing tiny, micron-sized LEDs which potentially offers a number of major advantages:

Firstly, the tiny LEDs are able to flicker on and off 1,000 times quicker than the larger LEDs this also means they can transmit data more quickly. Secondly, 1,000 micron-sized LEDs would fit into the space occupied by a single larger 1mm2 LED, with each of these tiny LEDs acting as a separate communication channel. A 1mm2 sized array of micron-sized LEDs could therefore communicate 1,000 x 1,000 (-i.e. a million) times as much information as one 1mm 2 LED.

Moreover, each micron-sized LED would act as a tiny pixel. So one large LED array display (e.g. used to light a living room, a