Using visible light as a medium for data transmission entails many advantages and
eliminates most drawbacks of electromagnetic wave which lies outside the visible
light spectrum (400 -800 THz or 375-780 nm).
The telecommunication industry is continuously expanding to meet the
human needs. However, bandwidth of EM/RF is limited and cannot keep up with the
demand, i.e. telecommunication companies are running out bandwidth to transmit.
Therefore visible light can be used as an alternative transmission medium to extend
the available bandwidth for transmission.
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Furthermore, visible light channel is free of charge. No company owns
property rights for visible light and thus no royalty fees have to be paid. Hence
visible light serve as an entirely free infrastructure to base a complex communication
network.
In certain areas such as hospitals and flights, EM/RF devices are prohibited to
avoid unwanted interference. Since VLC does not interfere with EM/RF, It can be
used as wireless medium for communication in those EM/RF prohibited areas.
In term of security, visible light can transfer data more securely than EM/RF
over short distances because it cannot be detected outside rooms or buildings, i.e.
light does not penetrate the wall. Thus, making it easy to secure transmissions against
casual eavesdropping (Haas, 2011).