Light gives off itself freely, filling all available space. It does not seek anything in return. It gives off itself and is not thereby diminished….

1. Li-Fi

2. Light gives off itself freely,
filling all available space.
It does not seek anything
in return. It gives off itself
and is not thereby
diminished….

4. Li Fi- LIGHT FIDELITY
Light based Wi-Fi
Use light instead of radio waves to
transmit information
No Wi-Fi modems
Li-Fi use transceiver-fitted LED
lamps

5. LED lamps serve dual purpose
 Lights up a room
 Transmit and receive information
Li-Fi is transmission of data through
illumination
Sending data through an LED light
bulb that varies in intensity faster
than a human eye can follow.

6.  Developed by Prof
Harald Haas, Dr
Gordan Povey, &
Dr Mostafa at the
University of
Edinburgh.
 Term coined by
Dr. Harald Haas
 Introduced at
TEDGlobal

7. CAPACITY
EFFICIENCY
AVAILABILITY
SECURITY

8. • Gamma rays -dangerous
• X-rays- hospitals
• UV rays- harmful
• Infrared – due to eye safety regulations it can
be used only in lower powers.
• Radio waves- Wi-Fi
• Visible light spectrum- Light, Inherently safe to
use

9. Visible light spectrum is 10,000 times
more than Radio wave spectrum

10.  LED is switched on and off faster since the
operating speed of LED is less than 1μs which
is faster than what the human eye can
detect, causing the light source to appear
continuously.
 This invisible on-off activity enables a kind
of data transmission using binary codes.
 Switching on an LED is a logical ‘1’,
 Switching it off is a logical ‘0’.

11. Such advancements promise a
theoretical speed of 10 Gbps –
meaning one can download a full
high definition film in just 30
seconds.

12. Serial
no
Parameters Wireless technologies
Li-Fi Wi-Fi
1 Speed more than 1 Gbps 150 mbps
2 Medium light Radio waves
3 Spectrum(Range) 10,000 times more
the radio waves
less
4 Cost No license required,
hence less expensive
More expensive
5 Security More secure(cannot
be hacked)
Less secure(can be
hacked)
6 Traffic control More(due to high
speed and
availability)
Less(signal becomes
weaker as traffic
increases)

13.  TRAFFIC LIGHTS
13

14.  Car headlights and tail lights
 Car-to-car communication
 Anti-collision systems
 Exchange of information on driving
conditions between vehicles.
 Traffic lights - city wide traffic management
systems.
 Car systems to download information from
the network and have real time information
on optimal routes to take.

15. 15

16.  In explosion hazard environments
such as Petro chemical plants, Li-Fi
can be used.
 Radio waves can produce sparks.

17. 17

18.  Wi-Fi-electromagnetic interference (EMI) with
sensitive radio equipment on the flight deck.
 On aircraft, Li-Fi enabled lighting will allow high
data rate connectivity for each passenger.

19. 19

20.  Radio waves are quickly absorbed in
water, preventing underwater radio
communications
 Li-Fi can enable communication
from diver to diver, diver to mini-
sub, diver to drilling rig, etc.

21. 21

22.  Exhibits in museums and galleries are
illuminated
 Li-Fi enabled lighting can provide localised
information within that light.
 This means that a visitor’s camera or mobile
phone can be used to download further
information regarding the object being
viewed from the light that illuminates the
exhibit.

23. 23

24.  Millions of street lamps
 Every street lamp could be a free
access point
 Street lamps could provide both,
illumination during night, and high
speed data communication 24/7.

25.  Light can't pass through objects
 Interferences from external light
sources
 A major challenge facing Li-Fi is how
the receiving device will transmit back
to transmitter

26.  The possibilities are numerous and can be
explored further.
 If this technology can be put into practical
use , every bulb can be used something like a
Wi-Fi hotspot to transmit wireless data.
 Cleaner, greener, brighter future

27.  http://www.ijstr.org/final-print/oct2014/Li-
fi-A-New-Era-Of-Wireless-Communication-
Data-Sharing.pdf
 https://www.youtube.com/watch?v=NaoSp4
NpkGg