- The input source can generate the information in any form which is to be converted in to communication format that is electrical form which can derive optical source like LED/LASER.
- The electrical modulator or source can provide modulation amplification signal processing etc. where as the optical source only provides electrical to optical conversion.
- In order to collect maximum light mechanical inter face are used at sender and receiver side like lens or prism.
- The transmission channel i.e optical fiber cable operates on the principal of total internal reflection.
- On the receiver side the optical detector or photo detector like pin diode/Avalanche photo diode is used thus electrical to optical conversion.
- The electrical demodulator can provides the signal processing and demodulate the signal.
Note:- Optical source is always forward bias where as optical detector is always Reverse bias.
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