The future is here!

Presented by

N.Manikandan (IInd B.C.A)

Contents

❖What is Li-fi?❖History❖Working❖Wi-Fi vs. Li-fi❖Applications❖Advantages❖Disadvantages❖Why Li-fi? (Conclusion)

What is Li-Fi?

❏ LI-FI is transmission of data through illumination, sending data through a LED light bulb that varies in intensity faster than human eye can follow.

❏ Li-Fi : Light Fidelity.

❏ Li-Fi comes under VLC (Visible light communication).

History★ Prof. Harald Hass is widely

recogni

-sed as the founder of Li-fi.

★ The technology truly began during

the 1990's in countries like Germany,

Korea and Japan where they

discovered LED's could be retrofitted

to send information.

★ Harald Haas continues to wow the

world with the potential to use light

for communication.

Harald Hass

Why only VLC?

Gama rays can’t be used as they could be dangerous.

X-rays have similar health issues.

Ultraviolet light is good for place without people, but otherwisedangerous for the human body.

Infrared, due to eye safety regulation, can only be used with low

power.

Hence the only thing left is The Visible light Spectrum.

Working…

Operational procedure is very simple, if the led

is on, you transmit a digital 1, if its off you

transmit a 0. The LEDs can be switched on and off very

quickly, which gives nice opportunities for

transmitting data. Hence all that is required is some LEDs and a

controller that code data into those LEDs.

How it works…

Working process…

Receiving and the transmission element:

The receiving elements are “AVALANCHEPHOTODIODE” and the image sensor.

Transmission element simply contains an LED lamp

which transmits the modulated light signals.

Applications:

Li-fi technology is still in its infancy. However some areas

where it seems perfectly applicable are :-

Traffic Lights Intrinsically safe environments Public internet hotspots Underwater communications (Rare) On airlines Hospitals (In some medical instruments)

Advantages :

Availability Efficiency High-Security Easy to use Harmless Fast data transfer

Disadvantages :

It cannot pass through objects. Interference or interruption in the path of communication.

High cost for installation. Presence of light is essential.

Why Li-fi?

Thank you

Any queries?