When telephony was first introduced, many were convinced that it would bring an era of communication traveling around the world in real-time. By the time landline telephones were introduced, this became possible. However, when cell phones started to gain ground, everything changed.
Cell phones started using radio waves invisible to the naked eye to receive and transmit information, but then came fiber optics and they changed the whole game altogether. Fiber optics work in a different way as they transmit coded information via a beam of light that passes through a plastic or glass pipe.
How It Works
Fiber Optic cables are made from ultra-thin plastic or glass strands called optical gibers. A single optical fiber strand barely has tenth of the thickness of human hair, but carries up to 25,000 calls in one instance. Contrary to popular belief, fiber optics is not new a new invention as it was originally developed in the 1950s for medical purposes. In 1960s, the technology made its way to communication, and since then, its impact has only grown in how easy and quick it makes communicating with people around the world.
So basically, light bounces repeatedly against the walls of fiber optic cables in a process that is called total internal reflection. Total internal reflection keeps the light in the fiber optic cables inside, even when photons hit the glass at shallow angles. The structure of the fiber optic cable also plays a part in keeping the light within the pipe. The middle part of the cable, i.e. the core, is the main part through which light travels. Meanwhile, the cladding is a glass layer wrapped around the core, with the sole purpose of keeping the light inside the core. It is generally made from shards of glass that have low refractive index, and depending on the use, the type of glass can vary accordingly.
Types of Cables
Optical fibers transmit light signals in modes. A mode is basically a path that the beam of light follows in the fiber optic cable. Single mode is the simplest form of optical fiber that features a thin core where light signals travel straight in the middle. These fiber optic cables generally carry telephone, cable TV, and internet signals, and can transmit information across 100 kilometers. Multi-mode optical fibers on the other hand, are nearly ten times thicker than single-mode. This setup allows light signals to travel in different paths indicated by the colors blue, green, and purple. They are generally used to transmit information in short distances, so they are commonly used in linking computers in a network.
Fiber optic cables today are the primary mode of transmitting long distance information as it is simpler, cheaper, and more reliable as compared to other modes. On top of it all, fiber optic cables help individuals and businesses leverage on far greater bandwidth and speed that makes them practical in all settings.