Fiber Optics 101

The Basics

According to The Fiber Optic Association, an optical fiber is a flexible, transparent fiber that is made by drawing glass or plastic to a diameter slightly thicker than that of a human hair.

The field of applied science and engineering concerned with the design and application of optical fibers is known as fiber optics.”

Fiber is used to transmit light from one end of the fiber to the other. In fiber optic communications, fiber allows for transmission over longer distances as well as faster data transfer rates.

Think about fiber optics as a tunnel or pipeline that the optical fibers are running through to bring light from one end to the other. The tunnel or pipeline, which is generally made out of a variation of plastic, is what encases several fibers together and bundles it into one compact strand. For this reason, fiber doesn’t have the loss that metal encasements do. This is because metal wires are especially sensitive to electromagnetic interference, whereas plastic is not.


The refraction of light is the premise that makes fiber optics possible.

When the light passes from air into water, the refracted ray is bent towards the perpendicular… When the ray passes from water to air it is bent from the perpendicular… If the angle which the ray in water encloses with the perpendicular to the surface be greater than 48 degrees, the ray will not quit the water at all: it will be totally reflected at the surface… The angle which marks the limit where total reflection begins is called the limiting angle of the medium. For water this angle is 48°27′, for flint glass it is 38°41′, while for a diamond it is 23°42′.” – John Tyndall (early 1850’s)

The idea of fiber optics had its roots as far back as the late 19th and early 20th centuries. At that time, light was being guided through bent glass rods to illuminate body cavities.

Note the following information found on Wikipedia which details the research conducted in the 50s and 60s.

“Although subsequent work was done, much of it was largely ignored until 1953. In 1953, Dutch scientist Bram van Heel first demonstrated image transmission through bundles of optical fibers with a transparent cladding. That same year, Harold Hopkins and Narinder Singh Kapany at Imperial College in London succeeded in making image-transmitting bundles with over 10,000 fibers, and subsequently achieved image transmission through a 75 cm long bundle which combined several thousand fibers. The first practical fiber optic semi-flexible gastroscope was patented by Basil Hirschowitz, C. Wilbur Peters, and Lawrence E. Curtiss, researchers at the University of Michigan, in 1956. In the process of developing the gastroscope, Curtiss produced the first glass-clad fibers; previous optical fibers had relied on air or impractical oils and waxes as the low-index cladding material.”

“Kapany coined the term fiber optics, wrote a 1960 article in Scientific American that introduced the topic to a wide audience, and wrote the first book about the new field.”


Fiber is useful in a variety of conditions. Obviously, it can be used for communication and in computer networking, due to its speed and lower attenuation. But in what other applications can it be used? Read on for more information…

Fiber optics can also be used as a sensor, and in some instances, it IS the sensor. They can be used to measure the intensity, phase, polarization, wavelength, or transit time of light in the fiber.

Fiber can also be used to transmit light into energy. This is the preferred method in healthcare settings, for example for use with an MRI machine, as they produce strong magnetic fields. Metal wires would not be feasible for such a setting.

The Bottom Line

Fiber is very versatile and allows for practical uses in a variety of settings where traditional wiring would not be feasible. Fiber is more efficient, faster, and is much more cost effective.

The future lays in the application and paring of materials in such a manner that it not only solves an existing problem, but provides solutions for many years to come.