(Sample Material) Study Kit on Current Affairs for UPSC Mains
Science and Technology: Li-Fi
Light-Fidelity is a new technology that uses light waves, instead of
radio frequency waves, as a medium to carry data. An improvised LED bulb,
functions as a router. It can provide internet access 100 times faster than
An ordinary off-the-shelf LED bulb connected to a device, which in turn
is connected to the Internet.
The Internet data flows in via the device’ into the bulb, and is carried
by light waves.
At the other end, light waves carrying the Internet data falls on a
receiver or a dongle which is connected to the computer.
‘The technology uses the frequencies’ generated by LED bulbs which
flicker on and off imperceptibly thousands of times a second to beam
information through the air, leading it to be dubbed the “digital equivalent
of Morse Code”.
Visible light spectrum lsavailable in plenty, unlicensed and’ free to
Double benefit of a bulb giving us light as well as internet access
Low interference leads to very high data speed
Li-Fi works under water as well
Not harmful, unlike RF that can· interfere with electronic circuitry
Light won’t pass through walls, making eavesdropping nearly impossible
LED illumination is already efficient and data transmission needs very
little additional power.
It can achieve about 1,000 times data density of Wi-Fi, since light can
be contained in an area
A disruptive technology that could transform business models, creates
new opportunities, and is poised to be a $113 billion industry by 2022.
The use of the light spectrum for Li-Fl overcomes the issues in
traditional wireless communication, like the shortage of spectrum and
network disruption because of interference as visible light spectrum is much
larger than the radio frequency spectrum.
In Li-Fi, anyone who has access to light can access the Internet. The
system also allows users to move from one light source to another without
losing their network connection.
Li-fi has a place in hospitals because it does not create interference
with medical materials.
In supermarkets it could be used to give information about a product, or
in museums about a painting, by using lamps placed nearby.
It could also be useful on aircraft, in. underground garages and any
place where lack of Internet connection is an issue.
Though the inability of light rays to pass through walls and similar
structures is seen as a major drawback of this technology but restriction by
walls provides more security to the network and eliminates the risk of the
signal leakage to eavesdropping.
Also Li-Fi requires devices be equipped with additional technology such
as a card reader, or donqle, to function. This gives it a “cost