Fiber optic communication refers to the method to communicate via optical fiber. Fiber optic communications is with a short history but with very rapid development in the past and now, and its impact has been in all aspects of communication field. Here we are going to give simple explanations of fiber optic communications.

First of all, why use fiber optics for communication? To answer this question, let us take a look at the need for information exchange nowadays. The trend is more and more information to be communicated and more and more information digitalized. The growing information needs a carrier with more bandwidth than ever before. What determine the carrier’s bandwidth? Its frequency. Which carrier is highest frequency? The light. Now we understand the light is with the highest information carrying capacity, that is why we use the light and optical fibers in nowadays communication networks.

We have realized light is the best information carrier, then we need to find a method to conduct the light as the way we like, we need to find a media - obviously the air will not fit – light will scattered and fade easily. After a lot of effort, finally people invented the optical fiber, the transparent flexible filament that could guide the light. Light in the optical fiber will follow the internal reflection law to transmit. The invention of optical fiber and fiber cables makes it possible for fiber optic communications.

Third, we need to find a optical transmitter and optical receiver for the light wave. Fortunately, when the optical fiber was invented, the key components for these devices, the laser diode and photodiode had been available at that time. That was around the year 1975, the first point-to-point fiber optic communication system was conducted in Bell laboratories. Since then, fiber optic industry developed quickly, the R&D story for fiber optic communication was over and the big business venture began. Nowadays, with submarine fiber networks connecting the whole world, fiber optic communication has connected the people from different places on the e