Let’s Follow the LiFi

200x faster than WiFi - is it time we update to LiFi?

In the endless race to technological betterment, is the new era of wireless internet about to begin? LiFi may well be about to take the stage, and with it will come a world only familiar to us through films of science fiction.

So what is it?

Well, LiFi works in a similar way to Wi-Fi, which sends data via small changes in high-frequency radio waves that the router sends out. These are more akin to the microwaves than the stuff Heart FM transmits over, which is why some old dodgy microwave ovens can actually interfere with your internet connection. The essential difference is that LiFi sends information via waves of visible light. In a sense, this means you can ‘see’ your wireless internet. Unfortunately, this doesn’t mean we will be treated to a technicolour, strobe-lighting display every time we load up Facebook. The data is sent over intensity and colour changes too minute for us to detect. All you will see is essentially a modified LED torch, or rather, your LiFi router. Your computer can pick up these changes in the light through a photocell (kind of like a small solar panel).

Why is this going to be better than Wi-Fi?

The answer is straightforward: speed. Simply put, because LiFi uses the visible light range, which is much broader than the radio range, it can operate considerably faster. If you’re into tech then the stat of 224 gigabits per second, which is the data transfer speed some researchers have reached, may mean something to you. If not then the quote from Forbes of “200 times faster than Wi-Fi in a work environment” may be easier to comprehend. Yes. 200 times faster. Now, whether or not we actually need data transfer of that speed is another question. I don’t know about you, but I don’t regularly stream multiple HD films at once. It is arguable that it would be of real benefit in a business setting, but personally I’m not certain of the necessity or need for this in a household. But hey, people probably said that about the Internet once.

This technology has taken years to create and bring down to a size that can be commercialized. The company leading this charge is PureLiFi, headed by Harald Haas, the (self-claimed) inventor of LiFi. It was PureLiFi which presented the first commercially available LiFi system called Li-1st at the 2014 Mobile World Congress.

However there are many improvements to be made and problems to be overcome. One such obstacle is that Li-Fi cannot go through walls.
Since radio waves have such long wavelengths, they can quite easily go through walls, windows etc. which is why your radio works indoors, and why your Wi-Fi can be used all round your house. But, in the same way your kitchen light doesn’t illuminate your bathroom, a Li-Fi router (basically an array of LED lights)  in a given room, is only going to be useful to devices in that room, and even more specifically, those in line of sight of it. So not only do you need to be in the same room, but if something were to block the signal eg someone walking past, then your internet will cut out.

Suddenly, LiFi looks pretty terrible. Or at least, like something that won’t fit in at the moment. It will require a world with an abundance of LED lighting as well as plenty of photocells. But then, are we very far away from such a world? Many modern houses have LED lighting, and photocell technology is racing ahead, with some screens themselves having photocell capabilities inbuilt. One day, every electronic device could have a solar cell and all our lights could be LED based. Such a future would be the Golden Age of LiFi. An additional beauty of LiFi lies in its use of photocells, which allows the device to be charged from the light itself, like a solar panel, while also being connected to the internet, with data being transferred via the tiny changes in the light.


Imagine, your smart-watch face equipped with a photocell, automatically connecting to superfast internet anywhere you’re in man-made light: in your home, a coffee shop, a supermarket. Your laptop could charge through a photocell on the back, as well as picking up untold internet speeds.

Imagine all your electronic devices connected to the Internet of Things through only the lighting in your house. Now that would certainly be a fascinating future.

About Tom Smith
Tom Smith is an 18 year old from Kent, who is looking forward to studying Theoretical Physics at university. Tom loves all things physics, from Quantum Mechanics to General Relativity. He also has a political streak, winning his school's mock election leading a libertarian party. He spends his spare time hopping between Atlas Shrugged and the Feynman Lectures.