If, however, the angle of incidence of propagating beams is less than the critical angle, then part of the optical power is lost to refraction, and propagation over long distances cannot occur. When the light signals reach the receiver, the light detector converts them back into electronic signals. The demodulator converts the electronic signals back into their original video, audio, data, or other format. The electrical interface displays the user output. 2.2 Benefits Optical fiber is faster and more secure than copper wire.
Light signals suffer much less attenuation over distances than electronic signals do.
This eliminates the need to periodically retransmit signals. Fiber optics can carry much more information than copper wire. Fiber optic systems are much freer from interference, suffer little transmission loss, and are not affected by lightning. Fiber optic systems offer much more privacy, as they cannot be tapped without detection. For a fiber carrying just one channel, speeds can reach 10 Gbps.