Li-fi: a new way of delivering data
A new method of delivering data, called Li-fi, uses the visible spectrum rather than radio waves and can be a hundred times faster than wi-fi, reaching speeds of up to 1Gbps. The Li-fi only requires a standard light bulb, such as LED, an internet connection and a photo detector. The technology is expected to reach the market within the next three or four years.
The term li-fi was first coined by Prof. Harald Haas from Edinburgh University, who demonstrated the technology at a Ted conference in 2011. The talk reached nearly two million viewers and showed a LED lamp streaming video. Prof. Haas envisioned a future when billions of light bulbs could become wireless hotspots.
One of the advantages of the li-fi is that, unlike wi-fi, it does not interfere with other radio signals, therefore, it could be used on aircraft and in other places where interference is an issue.
The light spectrum is 10,000 times larger than the spectrum of radio waves, thus providing a long service life. However, it cannot be exposed to direct sunlight, because of the risk of interference with its signal. Also, its use is still limited to places where it can work as a supplement to wi-fi networks, such as in congested urban areas or places where wi-fi is not safe, such as hospitals. So far, the technology cannot travel through walls.