With reference to Visible Light Communication (VLC) technology, which of the following statements are correct?
- VLC uses electromagnetic spectrum wavelengths 375 to 780 nm.
- VLC is known as long-range optical wireless communication.
- VLC can transmit large amounts of data faster than Bluetooth.
- VLC has no electromagnetic interference.
Select the correct answer using the code given below:
[UPSC Civil Services Exam – 2020 Prelims]
(a) 1, 2 and 3 only
(b) 1, 2 and 4 only
(c) 1, 3 and 4 only
(d) 2, 3 and 4 only
Answer: (c)
Explanation:
Visible Light Communication Technology
- It is a wireless method that enables high-speed transmission of data with visible light.
- It makes use of Visible Light spectrum. It occupies the spectrum from 380 nm to 750 nm. Hence statement 1 is correct.
- It enables high-speed internet access primarily in the indoor environment.
- It works on the principle of intensity modulation of existing solid-state lighting infrastructure often provided by light-emitting diodes.
- The nature of light is that it is unable to pass through opaque walls. Hence, VLCT is used in indoor environment/short range. Hence statement 2 is not correct.
- Li-Fi can transmit large amounts of data faster than Bluetooth and wi-fi. Hence statement 3 is correct.
- VLC systems operate at optical frequencies and emit no electromagnetic interference. Therefore, it can be used in Healthcare services. Hence statement 4 is correct.
