How Does Optical Fiber Work?

While fiber optics was invented three decades ago its use significantly increased over the last 20 years and the long-distance telephone industry relies very heavily on this technology now. In addition to this, fiber optics is also used across the world in internet communication networks. When fiber optic technology is used in place of copper for long distance telephone cables and internet transmission, it reduces the cost considerably.

No copper wiring exists in these installations for transferring data; light is used as the medium to carry this information. Since the speed of light is very high, this technology has gained popularity and fiber optics are now used in different types of communications systems. Before understanding how optical fiber works, we need to understand what it is. Here is some more information about it.

Understanding what fiber optics is

Fiber optics make use of light to transmit information via cables made of opticalfiber. The information is first coded into the cable’s light which allows it to move at very high speed and provides instantaneous communication. In a vacuum, light travels at a speed of 300,000 km/second; however, fiber optic cablestransfer it at 2/3rd that capacity, which is also extremely fast. Specially-designed cables carry the light and regular copper wiring cannot perform this function.

About fiber optic cables

Fiber optic cables used in standard systems have threedifferent layers:

  • The cladding or the exterior layer is specifically designed to prevent the optical layers that lie within, from becoming damaged.
  • The second layer has a mirror-like internal surface and has glass fibers. The special structuring helps ensure the light that’s being carried through the fibers remain contained within the cables. Without this internal surface, the light can escape and cause loss/corruption of data.
  • The core layer is made of optical fiber mesh which has numerous glass thread strands.These fibers are extremely thin and have the capacity to support literally thousands of phone calls. A single cable can hold anything between two to 1000 strands based on what the communication requirement is.


Fiber optics- the working

Light travels down fiber-optic cables by bouncing constantly off the internal walls. Each tiny particle of light (photon) bounces down this pipeas smoothly as a sleigh sliding down an ice run. Most people feel that if a beam of light is traveling through a clear glass pipe it will just leak out of the edges. However, when the light hits the glass at an extremely shallow angle (<42 degrees) it simply gets reflected back just as if the glass were actually a mirror. This particular phenomenon is referred to as total internal reflection and that is one of the things that helps contain the light within the cable.

The structure of the cable is the other aspect that helps keep the light contained within it and is essentially made of twodistinct parts. The cable’s main part is referred to as the core and that’s the area the light travels through. But the cladding has a much lower refractive index and as mentioned earlier, that is what keeps the light in the cable and facilitates in the speedy delivery of the coded information,

If you are upgrading your older telecommunication system to a new fiber optic one, you need to ensure that you hire atelecommunications company specializing in fiber optic installation.