Fiber Optics: Messages In A Light Beam

Feb 1, 2021 By Ritali J.
Ritali's picture

Have you ever wondered how your texts and emails travel across the world within seconds?

Fiber optics is a revolutionary technology that sends information in the form of light pulses through flexible fibers made of glass or plastics. 

There are networks of fiber optic cables that criss-cross our world, running underground on land and across oceans. They have enabled the growth of the internet at a rapid and massive scale.

This technology would not have been possible without Narinder S. Kapany, a pioneer in this field. Dr. Kapany, who is known as the father of fiber optics, passed away at the age of 94 on December 3, 2020.

Let’s explore how fiber optics operate and how Dr. Kapany’s work changed our world.

How Fiber Optics Cables Work

Think of the time you may have communicated with your friend by turning your torch "on and off" to send coded messages. Similarly, light pulses are sent through the cables as binary codes (earlier article here) which is a language computers understand. 

A fiber optic cable is composed of thousands of glass fiber strands, each one as thin as a single human hair. The cable is made of two main parts. The core is where the beams of light move through. Meanwhile, the outer layer of the cable is called a cladding, and it helps the light pulses stay within the core. Because the two layers are made of different types of glass, light is bent (or refracted) when it moves through the cable.

The beams of light reflect off of the cable walls and move through the core in a zig-zag pattern. This phenomenon is called total internal reflection and drives the mechanism of fiber optic technology. However, the signals weaken as they travel over long distances, so amplifiers are used to increase the strength of the light signals over certain distances.

Fiber optic cables do not let light escape easily, which decreases the chances of accidental interactions with outside signals. Since light cannot easily enter the cable from the side either, fiber optic cables provide high security for data, in addition to high bandwidth and long-distance communication.

Dr. Kapany's Legacy

Dr. Kapany was a prominent academic scientist in fiber optics during the mid-1900s. In fact, he named the field of “fiber optics,” and also wrote the first book on this technology.

Between 1955 and 1965, Dr. Kapany authored 56 research papers, or 30% of all published material regarding optical technology at that time. He also started several fiber optic technology companies to further his research. Throughout his career, Dr. Kapany urged governments and corporations to research further into fiber optics.

Today, fiber optics technology is used in communications, military and satellites, biomedical surgery and endoscopy, computer networks, lasers, solar energy, and pollution monitoring. For example, telecommunication services that people use every day, such as the internet, television, and phones, are all delivered through fiber optics cables.

The advantages of this technology are its high bandwidth, long-distance interconnectivity, and data security. As the world advances, we can only wait to see how fiber optics, technology, and new research will continue to revolutionize our world.

Sources: NY Times, UCSC, YouTube,


BradleyBrown's picture
BradleyBrown February 12, 2021 - 9:06am
i never knew that!
bluespark's picture
bluespark February 3, 2021 - 12:27pm
This is amazing!