The whole journey from Wi-Fi to Li-Fi..

“Let there be light” and there it was!

I think light is one of the greatest creation of God and he made it so easily, just like that. It took thousands of years for man to figure it all out, that it was the Electromagnetic spectrum.

Electromagnetic spectrum

The Electromagnetic spectrum is just a bunch of wavelengths simply said, a collection of ‘different type of lights’; some visible some not so visible, some visible only to some devices only.

Just like your book collection at home, these ‘lights’ are arranged in an order.
The EM spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency or vice versa.

It goes like this: radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma rays.

Actually, you are reading this sentence because of these so-called ‘waves’.

Seriously what are they…?

Well, not all the waves, just some part of the spectrum is used up.
If you are curious enough, you might have asked :

“I am using the Internet, downloading PDFs, and much more (), but how?”

“The servers are mountains away but how can I download data if it is so far from my home?

How do I watch YouTube LIVE videos and stuff?”

Let us walk through the thought process.

See, basically, you use data in those YouTube videos, right? So you need to get the data from those servers to your computer.

First of all, you need something to carry all those data, like a bus carrying students to school. Well, the ‘genius people’ has figured it out to use waves from the electromagnetic spectrum to carry all those data.

The waves that carry data for the internet are the same kind of waves used for radio and TV. It is also similar to the waves as for visible light, x-rays, and gamma rays.

Factors such as frequency and wavelength keep these waves different just like engine power and fuel keeps various types of busses different.

The data sits on the bus (waves) and travels to your computer.

So what road does the bus (waves) use?

The bus (waves) uses coaxial cables, optic fibers, broadband connection, etc as the road to reach your computer.


OR instead of the cables, we get internet on our mobile SIM.
Most of us use mobile data. Waves that contain data jump from Mobile tower to tower till they reach your SIM.

JioFi 4G Hotspot. THIS IS A GOOD ONE.

I have a SIM with a 4G connection on my phone. It is pretty fast sometimes, but mostly slow and erratic. Why? I’ll get to it in a moment.

Then I turn ‘ON’ the Hotspot in my Smartphone which contains the SIM to connect my laptop to it via WI-FI.

What is Wi-Fi?

WI-FI stands for Wireless Fidelity.

‘ Convenient ‘ is the word for WI-FI. All your Smartphones, laptops and other portable devices can be connected at any convenient location within the premises.

And if you have an iPhone already and by chance you had to buy its latest version out of curiosity, you don’t have to worry, simply turn ON the Wi-Fi and click connect, if the iPhone allows you () to do so.

With WI-FI, Internet can be accessed from anywhere, ie. Bus, train, park, etc even in the toilet (PRO TIP: Don’t use your phone in the toilet too much )

WI-FI is stretchable :
It is easy to add more wireless devices with the current hardware settings at NO cost and time.

WI-FI can keep your pockets safe:

In WI-FI, all your devices can be added at NO cost, unlike those tedious cables which need manpower to do the job

Standardization of Technology:

Thank God, the Wi-Fi technology has been standardized for all countries, it is very easy for all sorts of mobile devices to connect to WI-FI regardless of the location.

So before we jump onto LI-FI, let’s summarize WI-FI.

Simply put, WI-FI is:

• Convenient
• Simple
• Mobile
• Expandable
• Efficient
• Cost-effective
• Standardized technology.

The downside of WI-FI:

I am a victim of one of the greatest disadvantages of WI-FI.

It is S P E E D.

We cannot get the same speed at all locations. It’s so irritating, you know, sometimes I walk around with my mobile to get the right spot to get the right speed.

One time, I almost threw my Smartphone out of the window to get speed.


There is a limit for distance to connect WI-FI signals.

Wireless networks also have a HUGE chance of jamming and interference due to external factors such as fog, rain and dust storms.

Now the thing I hate the most about WI-FI is when too many people in the premises use simultaneously, the WI-FI becomes overloaded.

And I often get to be the unhappy kitty when I donate my data through hotspot to my friends, there’s got to be a way to overcome this. ()


WiFi router has various encryption methods to secure our network password. It needs to be done with proper configuration before using the WiFi network.

But I have a fun time setting crazy passwords. (Here is the link to crazy passwords)

To summarize:
The disadvantages of WI-FI:
• Dips in speed.
• Unreliable.
• Questionable security.

So, something has to be done to get the disadvantages of WI-FI solved for, but before that, I would like to wonder if there is a bigger picture of the problem.
I want to ask some questions.

How many people use the internet?

Where is all the data stored?

What if we run out of data?

The population is on the rise daily and why isn’t the radio spectrum of the EM spectrum not getting filled up with all the radio communications and data transfers taking place worldwide??

What happens to security when everything is becoming digital?? Photos, passports, etc..etc… All of our memories are digital. What if bad people hack them out?

Would someone steal our memories??

There was a study done in 2015 by Huawei Technologies Sweden to estimate the percentage of global electricity consumption by Communication Technologies worldwide.

To my surprise, the analysis showed that in the worst-case scenario, Communication Technologies will consume a whopping 51% of global electricity in 2030.

This would happen if enough innovations and engineering is done to improve the electrical efficiency of wireless networks and fixed access networks/data centers.

Also to my surprise, it is predicted that Communication Technology could have a thrilling 23% part in destroying the world through greenhouse gas emissions in 2030.

Guess what, not only humans create data.. your toaster, your car, your bike, you TV, probably your toilet is going to produce data too(in the future). Just wait for it.

The study also explains Electricity usage from Communication Technology into four categories:

(i) Consumer devices such as personal computers, mobile phones, Smartphones, TV and Home entertainment systems.

(ii) Network infrastructure: LAN, WAN,…etc.

(iii) Datacenter computations and storage.

(iv) Production of the above categories.

Regarding impacts of production, left out amongst others include:

1. Printers and multifunctional devices;

like Smart printers

2.Digital and video cameras;

3.Music and video players (also similar devices)

like smart TV’s

4.Network connected white goods. ( white goods are electrical goods used at homes such as refrigerators and washing machines, typically white in color.)

like smart AC.

5.Smart thermostats;

like this thing, it is also compatible with alexa!!

6.Home energy management;

7.Security systems;


8.Personal drones;


10.Driverless automobiles: even bikes..

11.Portable batteries, “power banks”

So, in short, these wireless networks have an Enormous carbon footprint (the footprint of the size of a dinosaur)

By the way, 2030 is just 11 years away.

Now that is an issue, isn’t it curious buddy?

I have always loved the quote,

“To kill two birds with one stone”.

(Disclaimer: I Love Birdies. I seriously have nothing against them)

What I mean to say is, when we innovate something, it has to be used for multipurpose. It has to solve Problem1, Problem 2 and Problem 3 or more, that way the product becomes most efficient.

Thank Science; we’ve just got the product for the job.

I want to walk you through the thought process to get the gist of the curiosity.
Let us put our science caps once again.

You see, the Radio waves carry around all the data for all the wireless networks now.
The ‘Radio’ region of the EM spectrum seems to get saturated. It has the burden of A LOT OF DEVICES (They say by 2020, we will have 80 billion IoT devices).

Phew!!! That is a lot.

A lot of the genius people out there were curious to ask if we could make the radio waves could act like busses to carry data, why don’t we do the same to the VISIBLE SPECTRUM???

“Why don’t we design something to do with light??”

They thought.
The visible spectrum to radio spectrum is like comparing the sun with the earth.

As I said in the beginning light is everywhere and we need light every time. It would be great if we could use those LED light hanging around at our homes to some good use.
These LEDs require electricity anyway, so why don’t we make them send data too??

BOOM!!, the LI-FI is born.!!!

But first, what is a LED?

In the simplest terms, a light-emitting diode (LED) is a semiconductor device that emits light when you turn on the switch(pass electricity).
Light is emitted when the particles that carry the current (known as electrons and holes) combine together within the semiconductor material.

I can’t go deep to LED right now because it might throw us off-topic.

Now for more curious questions.. (PRO TIP: Hey curious buddy, never get tired of asking questions.)

Imagine a world where all the LED’s can be converted into internet sources.
What if light and data used the same power source?? (Nice idea for being MULTI-PURPOSE)

Could we offer bandwidth like Never known before?

The term Li-Fi was first introduced by Harald Haas during a 2011 TEDGlobal talk in Edinburgh.

Harald Haas

How does Li-Fi work?

Here it goes.
This is the skeleton of the journey of the ‘data’.
Data is generated from a device and then transmitted through a transmitter, travels in a medium and then received in a receiver.

Now data can be generated in a server and the LED acts as a transmitter. There is a photoreceiver at the receiving end to receive the data from the LED.

So how does LED transmit data?

Do you remember the LED of a Television remote controller? You can see a red LED shining right?
You see, when you click on a button on the remote control, the LED sends a signal to the TV by blinking ON and OFF. It happens so fast. The ON and OFF are received by the TV as signals as zeros and ones.

So it is the same situation here, only that the LED used in LI-FI is LED already used in your home RIGHT NOW.

But how do I convert the LED in the room to LI-FI??

They say you need to just plant a chip to it and Vola!
Your LED is a transmitter now.

The receiver on the other device captures the changes in amplitudes produced by the chip on the LED. You don’t have to worry about getting a disco light ON and OFF situation in your bedroom as the tremendous speed of ON and OFF is too quick for the naked eye to captures.

To give a more modern view, you can connect a chip to your LED, turn it ON. Nowadays a USB dongle is available to connect it to the system which needs to receive the data. The dongle can connect to any USB device.

And there is the HD 1080p video playing in your laptop.

To summarize,

Construction and working of Li-Fi.

Working of Li-Fi.

The signal to be transmitted at the transmitter section can be modulated with a particular time period and then send the data using your LED in 1’s and 0’s form. I would like to remind you that the flashes of LED bulbs are denoted using 1’s and 0’s. At the receiving end, a photodiode captures the LED flashes, and then strengthens the signal and then gives the output.

So you have light plus data. Perfect day.

Not yet…

The main feature of this technology includes fully networked, bidirectional and high-speed wireless transmission.

And I am going to bomb you with yet another….

The range of data transmission in Li-Fi is 100 times faster than Wi-Fi.

Yeah, you heard it… 100 times faster.

That is like downloading 20 movies in the blink of an eye.


To stir up your imagination, imagine yourself (WI-FI) being in a race with Usain Bolt(LI-FI) and guess what happens…
Duh…Bolt wins.

But how???

The frequency of the radio waves used in Wi-Fi is of order 5GHz (maximum of 60GHz). Whereas, the Visible light spectrum used for Li-Fi has a frequency of about 500THz.

Simply put-
The maximum data rate depends on factors like power, bandwidth, and ambient noise.
Since Wi-Fi uses radio waves and Li-Fi uses light to transmit data, light allows for far more bandwidth, more allowed power, and then lesser background noise.

Radio waves, which are used by Wi-Fi, have such limitations, and that is why Li-Fi can, in theory, move data faster.

That’s about 10000 times more than Wi-Fi.

That is why Wi-Fi will lose the race.
In fact, Harald Haas (Inventor of Li-Fi) says,” The 3RD INDUSTRIAL revolution can be LIFI.”

What are the Advantages of Li-Fi? Or better yet… Let me frame the question as “Why is Light Fidelity better than Wireless Fidelity?”

1.Wi-Fi has a very limited Bandwidth (radio spectrum) while the Visible spectrum used by Li-Fi has a very L A R G E bandwidth.

2.The Speed of LI-Fi can be greater than 10 Gbps while Wi-Fi is just 150 Mbps

3.The amount of data that can be carried at a time by Li-Fi is higher than that for Wi-Fi.

4.The Security factor of Wi-Fi is questionable , but perfect for Li-Fi.

5.The power consumption for Wi-Fi is high and zero( or Minimal is the right word) for Li-Fi as the same power used to light the room is used for data transmission.

6.Li-Fi has minimal impact on ecology compared to Wi-Fi.

7.Li-Fi costs very less compared to Wi-Fi in terms of copper wires, other equipment, and electricity. If only you knew how many hundreds of kilograms of copper every single office building uses for data communication you would understand how much big of a deal this is !!

8.Undisturbed by radio interference.

9.Li-Fi is not harmful to humans, as it does not generate an electromagnetic environment like other wireless communication systems. Hence it can be easily used in radiation-sensitive environments like hospitals and Petrochemical plants.

To summarize, Li-Fi helps in following key areas:
Increase in CAPACITY.
Increase in EFFICIENCY.
Increase SECURITY.

Now for the next obvious section

What are the Disadvantages of Li-Fi?

• Range of Wi-Fi is medium but low for Li-Fi. When you move out of the light – NO DATA, sorry.

• This can mean that your phone won’t receive an email when it is inside in your pocket.

• Internet could not be accessed without a light source. This could limit the locations about which Li-Fi could be used.

• It uses visible light and light cannot penetrate walls, therefore, the signal’s range is limited by physical barriers.

• Other sources of light could disturb our signal. One of the depressing drawbacks is the interception of signals outdoors. Sunlight could interfere with the signals, resulting in an interrupted Internet.

• A whole new infrastructure for Li-Fi has to be constructed.

• It needs specialized hardware for its implementation which is difficult to obtain on a big scale.

• The current technology must be upgraded for the common public to use it and If the public needs to use it, we are talking about a H U G E up-gradation.

• The range of Li-Fi is limited by two major factors:

1.Dispersion of visible light

2.The inability of light to penetrate opaque objects.

• The popularity of Wi-Fi is a major factor in preventing the use of Li-Fi. The disadvantage of Li-Fi makes it a pretty difficult task to replace conventional Wi-Fi networks.

Curious Buddy, I am guessing a few questions that you might have, but if you have more the comment box is always open for you please.

‘Should I have the lights ON all the time to get the data during day time also?’

The answer is yes. If you want the data during the daytime you need to keep the lights ON.
You don’t need to buy an entirely new LED for this… You can just buy a chip and fit it into an illumination device and make it capable of both illumination and wireless data transfer.

If you can dim the brightness of the LED somehow during the daytime it might help, as the receiver picks up only the changes in the amplitude and not the brightness.

Do we have to stay totally under a LED to get the data?

The answer is YES you need to stay under a LED but you don’t have to stay under only one LED, if another LED in your room has Li-Fi then you can move from the region of one LED to another and still stay connected from the other LED. Pretty cool huh..!

Is Li-Fi better than 5G?

Oh yeah, it is. The first reason being you to implement 5G cell towers needs to be constructed for every 8 homes because 5G offers very little range.
Secondly, that is too much dosage of RF radiation and too much of anything is BAD.

you are going to see many of these when 5G comes up. not worth it.

What happens when there are two different Li-Fi users in the same room. What will happen if the detector sense light from two different sources?

Will there be a data malfunction due to constructive or destructive interference of light?

Well, the light signals could not be coherent, so there is no possibility of any destructive interference.

Even if they were coherent sources, several other conditions have to be satisfied: the 2 sources would have to be very close in frequency and both signals would have to arrive at the detectors at very similar angles such that the interference was similar across much of the detector.

Even then, modulation would still exist, although there would be distortion and mixing, so the end result would depend on the modulation scheme.

What is the price of Li-Fi?

Since the product is still in its Research and Developmental stage ( not commercialized yet), giving a straight number for a price is a bit difficult. However, there are a few project kits available.

The company pureLiFi ( is currently working on miniaturizing its Li-Fi technology.


Eventually, the end consumer will see minimal or no cost associated with Li-Fi as the ambition is to have Li-Fi embedded in every wireless mobile device.

Their end goal is to have Li-Fi in every mobile device. This means that the technology will be made affordable for handsets, tablets and laptops, TV or anything that uses the internet.

Applications of Li-Fi. (Futuristic and non-Futuristic)

1.Cars can communicate with headlights. With Elon Musk and his men pumping up their brains on automatic and sci-fi cars that talk to each other are around the corner probably be around us by 2020. Now the cars have a headlight and traffic lights have lights too. It is only a matter of inserting some chips here and there before they begin communicating with each other.

This superfast communication can prevent accidents and prevent road maniacs and also avoid reckless driving. More the control we give to the computers safer we are (safe from human errors) and therefore giving these computers an effective way to talk to each other should be our priority.

2.There are godforsaken places on our planet that don’t allow the usage of Radio waves due to safety concerns. Mobile phones are not intrinsically safe, meaning that they have the potential to strike up a spark bright enough to ignite a vapor air mix. Oil refineries are vulnerable to such accidents so it is smart to keep potential sources of ignition far away.

lots of lights huh? source :

3.Super Li-Fi comes to the rescue in such cases simply because it does not use radio waves but just light. You might be familiar to “AIRPLANE MODE”. Ever notice that you cannot use mobile data when you turn ‘AIRPLANE MODE’ ON?

Well, the name ‘AIRPLANE MODE’ is used because you cannot use mobile data on the plane as all that radio waves that you sheepishly use to watch your favorite Game of Thrones (HD) video on your phone might just cost your life because all the airway communications are based on radio waves.

4.HOSPITALS- Li-Fi can be safely used in a few hospital applications. Li-Fi technology will allow a light communication network in corridors, waiting rooms, patient rooms and operating theatres, which will avoid electromagnetic interference issues from smartphones and Wi-Fi in hospitals. Li-Fi can also be used for real-time monitoring of the patient movements and vital signs without any twisty wires.

5.Li-Fi can help you have uninterrupted Live Videos of your favorite celebrities.

Li-Fi can help you talk seamlessly with your father on the other side of the globe. Happy Skype!.

You can find more applications here


You can email me @ if you want the PDF on Li-Fi Technology.

If you want a PPT on Li-Fi technology you can click here.

What’s happening to Li-Fi around the world?

Curious buddy, I want to conclude by quoting my good friend Wikipedia,

“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, mainly for technology evaluation.”

Disclosure: We are a website that requires compensation to operate like any other website on the internet. We may receive consideration for our reviews but we are totally unbiased and do not accept paid reviews or fake reviews claiming to be something we are not. This article contains affiliate links.

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