About Li-Fi:

Li-Fi stands for Light Fidelity, it is a wonderful wireless communication technology that is based on transmitting data packets using light.

Imagine being able to transmit data at the speed of light (god it is so cool !).

In terms of technology, it is similar to Wi-fi but the difference lies mainly in the spectrum of working. Wi-fi uses the radio wave spectrum whereas li-fi uses the light spectrum (which in itself consist of visible light, ultraviolet, and infrared spectrum).

So it’s clear that Li-fi works on a much broader spectrum than Wi-fi.

But before going further, let’s thank Prof. Harald Haas (University of Edinburgh), who coined the term “Li-Fi” at his 2011 TED Global Talk where he introduced the idea of “wireless data from every light”

Working:

Li-fi works using Visible Light Communications(VLC) (Now what’s this??).

This technology uses fluorescent lamps, the LEDs in the lamp are toggled between ON/OFF at a very high speed, this flickering is detected by photodiodes (a light-sensitive device). The flickering is normally invisible to the naked eye.

Lamp driver is responsible to get the data from the internet server and convert into light signals(mainly by controlling the frequency of flickering of the LED lamp).Interestingly this means you can convert the ceiling lights of your home and office into a light source under which you can experience high internet speed.

The lesser-known fact is that VLC was first introduced by Alexander Graham Bell when he invented the photophone (will talk about this in some other post).

Advantages of Li-fi over Wi-fi:

  • Since it uses visible light to transmit data, it gives a butt kick to the usage of routers(no more routers !).
  • On the other hand, Wi-fi uses the radio spectrum and each internet service provider uses their own bandwidth within the spectrum to provide internet, the US Federal Communications Commission has warned of a potential spectrum crisis because Wi-Fi is close to full capacity, Li-Fi has almost no limitations on capacity.
  • We know light cannot pass through walls, so naturally, it makes Li-fi less prone to be hacked(by someone next door).
  • Do you know why airlines don’t provide you with an internet connection or why they tell you to switch off your phones?, it’s all because airplanes are susceptible to electromagnetic interference(or in the simple sense it’s allergic to radiations). Li-fi doesn’t have these issues, as all it wants is light!. (it is said that Oledcomm has partnered with Air France to provide in-board internet using Li-fi).
  • Moreover, if you are someone who thinks that radiations are harmful to your health then switching over to Li-fi will be the best option.
  • In 2014, the Russian company Stins Coman started developing their own Li-fi modules, and their current module transfers data at 1.25GB/s (they are aiming for 5GB/s in the future). In the same year, Sisoft was able to transmit 10GB/s across a light spectrum from using LED lamps.

Does all this mean that you can download a movie in a second or two??

Well no, the speed of the internet is also heavily dependent on the internet service provider and on the web servers but the data transmission from the light source to your device will surely be very high.

So why don’t we see anyone using Li-fi???:

The major bottleneck of this technology is that it uses a visible spectrum and contemporary electronic gadgets are not adjusted for this technology. The other issues that come in are short-range(you need to sit close to the light source) and high installation costs.

The Li-Fi market was projected to have a compound annual growth rate of 82% from 2013 to 2018 and to be worth over $6 billion per year by 2018. However, the market has not developed as such and Li-Fi remains with a niche market.

I am Electronics engineering undergrad, truly passionate about learning and building technologies. I am a part of an innovation group IgnitedMindz @IIITD