Educational Resources

We are committed to providing educational tools for teachers and students looking to learn more about the basics of optical fiber, its composition, and its capabilities.

What is low-loss optical fiber?
Low-loss optical fiber is a flexible filament of high-purity glass capable of carrying information encoded within pulses of light over long distances with low attenuation (signal loss).

Who invented optical fiber and when?
Corning scientists Dr. Robert Maurer, Dr. Peter Schultz, and Dr. Donald Keck invented the first low-loss optical fiber in 1970. Inspired by their belief that information could be transmitted through light, Drs. Maurer, Schultz, and Keck spent four years experimenting with different properties of glass until they succeeded, creating the first low-loss optical fiber for telecommunications use.

Optical fiber was invented in response to what telecommunications challenge?
Optical fiber was our answer to consumer demand for increased bandwidth. Beginning in the 1960s, the telecommunications industry realized that the existing copper wire infrastructure could no longer keep up as communications traffic increased exponentially.

Why is optical fiber a revolutionary product?
Optical fiber revolutionized the telecommunications industry because it allowed for low attenuation (or reduction of signal strength) and, unlike copper, offered virtually limitless bandwidth. Because of those qualities, optical fiber has become the backbone of the networks that we use today to transmit voice, data, and video around the world.

What is the composition of optical fiber?
Optical fiber has three basic components: (1) the core, consisting of high purity glass that carries information through light waves, (2) the cladding glass around the core that inhibits light from escaping from the core by virtue of having a slightly different composition to provide lower refractive index, and (3) an outer coating to protect the glass from damage.

How does it work?
Encoded into a pattern of light waves, information travels through each optical fiber by a process of internal reflection. The waves move through the fiber from a given source to a destination such as a cable box where it is then decoded.

How is optical fiber made?
Inventing optical fiber was only the beginning. Our scientists then had to create an innovative process to produce a fiber that could be cabled, spliced, and connected to make it practical in the field. Corning’s patented manufacturing process begins by creating "preforms" of glass on proprietary vapor deposition lathes. These preforms are sintered into a solid, dense, transparent glass and subsequently drawn into coated optical fiber, as thin as a strand of human hair. Additional manufacturing steps test the fiber for strength at 100,000 pounds per square inch and fully measure its optical performance before shipment to customers.

What is the difference between single-mode fiber and multimode fiber?
Single-mode fiber has a smaller core than multimode fiber, allowing only one mode of light to move through it. This design was created particularly for telephony applications, where the fiber needs to retain each light pulse over long distances. Multimode fiber has a larger core, enabling hundreds of modes to move through it simultaneously. Designed for cost-effective operation over shorter distances, multimode fiber is used primarily for data communications in private networks.

How has optical fiber changed since its invention?
The first low-loss optical fiber was celebrated for having a total attenuation (or loss) of 17dB/km. Today, there are optical fibers with attenuation as low as 0.17dB/km, which translates to signal loss being 100 times better than the original. As a result, optical fiber is the preferred medium for fast, reliable, and increasingly economical communications networks.

What are some examples of fiber products?
Corning holds hundreds of patents on the different types of fiber that support practical applications for today’s telecommunications market needs. We manufacture industry-leading fibers that connect continents, countries, cities, and citizens around the world. Corning's products include an array of single-mode and multimode fibers for all of today’s applications.

Where is optical fiber used today?
Today, optical fiber provides the infrastructure for broadband connectivity all around the world. We continue to design practical applications of optical fiber for enterprise, fiber to the home (FTTH), access, long-haul, and submarine applications to connect communities, countries, and continents.

How does optical fiber affect me?
Optical fiber serves as the high-tech backbone that supports all the communications and interactive technology we use every day. Because of the global fiber network, you have instant access to voice, information, and video through devices such as smart phones, computers, high definition TV, GPS, and game systems through which you get directions, send e-mail, conduct research, join social networks, shop, and download music, movies, and more.

What helps us predict how fiber will be used in the future? 
As has been the case from the very beginning, one driver that shapes the future of optical fiber is market demand. In response to new challenges and the increasing demand for broadband connectivity, our scientists will continue to discover innovative solutions as they are needed within the marketplace, and our engineers will continue to create new, practical glass technology.

What breakthrough applications are already happening? 
Optical fiber continues to create new opportunities in how we live, work, and play. Innovations such as Cloud Computing, Optical Port Technology, and Passive Optical Networks (PONS) will enable us to partner with technology in a way never before possible.