The Oxford dictionary defines a light-bulb moment as a “moment of sudden realisation, enlightenment, or inspiration”. Fitting, then, that scientists recently discovered the internet could be transmitted via light bulb.
Soon the day will come when you check into a hotel, or slide into a café chair, and ask staff for their “LiFi” code.
And the internet access granted by that code will be many, many times faster than what you now get via WiFi.
WiFi, of course, uses radio waves, just like mobile phones, televisions and radios. Radio waves are comparatively antiquated, both in the limits on the data speeds they allow and also in the amount of wireless data they can transmit.
LiFi exploits light – it uses LED bulbs as the medium through which it transmits networked, high-speed communications data – and looks set to produce truly astonishing download and upload speeds.
Already, researchers at Oxford University – which has led the way in developing LiFi – have achieved connections in excess of 200Gbps.
Imagine, in the space of one second, being able to download every single episode of The Sopranos, Breaking Bad, South Park, The Wire and I Dream of Genie. Oxford researchers have indicated that is just the tip of the iceberg, forecasting that speeds of at least three terrabits per second will be possible with LiFi.
LiFi would work just like all visible light communications – switching light sources on and off rapidly and within nanoseconds. That means it’s too quick to be noticed by the human eye. While LiFi bulbs would need to be kept on to transmit data, the bulbs could be dimmed to the point that they were not visible to the human eye – and yet still fully functional.
That means the technology wouldn’t be annoying in a household – with clever engineering able to make it non-intrusive.
The constant and huge growth of mobile phone usage worldwide is placing evermore pressure on internet radio waves. Cisco has predicted that by 2019 more than 10 billion devices will exchange about 35 quintillion bytes of information per month. Such a volume of data transmission would cause significant congestion of existing radio waves.
This is where LiFi comes in. With light there is no concern about being limited to a set of radio frequencies so, in the short term, LiFi looks likely to complement WiFi networks, easing the strain on the radio frequencies.
One of the key developers of LiFi, Harold Haas, recently said in a TED talk that he believed one day every LED lightblub could be used for massively high-speed Internet.
“We have the infrastructure there. We can use them for communications,” Haas said. “All we need to do is fit a small microchip to every potential illumination device and this would then combine two basic functionalities: illumination and wireless data transmission.
“In the future we will not only have 14 billion light bulbs, we may have 14 billion LiFis deployed worldwide for a cleaner, greener and even a brighter future.”