What Is Fiber Optic Cable, and How Does It Work?

By: CableOrganizer®

fiber optics

You may know that fiber optic cabling is important to applications like the internet, telephone systems, and cable TV, but have you ever wondered about how it actually works? Or why it’s so perfect for transmitting data? All of us here at CableOrganizer® thought you might be looking for answers to these questions. Read on to find out what exactly goes into making fiber optic cable, and just how much it’s capable of.


Fiber optic cabling is based on optical fibers, which are long, flexible, hair-width strands of ultra-pure glass. Optical fibers are formed when preform blanks — portions of specially manufactured glass — are heated to between 3,000° and 4,000°F. These are then drawn out at a rate of up to 66 feet per second. As an optical fiber is pulled, it is constantly monitored by a laser micrometer, which ensures its diameter is perfectly uniform from start to finish.

For optical fibers to transmit data over long distances, they need to be highly reflective. On their way to being spooled, newly pulled glass fibers pass through coating cups and ultraviolet ovens, which respectively apply and then cure the thin plastic buffer coating that creates a mirror effect within the fiber.

The finished optical fiber is then extensively tested in a wide range of categories, including Tensile Strength, Refractive Index Profile, Fiber Geometry, Attenuation, Bandwidth, Chromatic Dispersion, Operating Temperature, Temperature Dependence of Attenuation, and Ability to Conduct Light Underwater. After testing has proven that the newly manufactured optical fiber meets all standards, it is sold for use in fiber optic cabling.

Depending on what type of application it will be used for and how much data it will need to transmit, fiber optic cable can be built around a single strand of optical fiber, or larger groupings of it. To assemble a complete fiber optic cable, the strand or cluster of optical fiber is placed at the core. It is surrounded by a loose tube of PVC, which leaves the fiber room to bend when being routed around corners and through conduit. The loose PVC is then covered with a layer of shock-absorbing aramid yarn, usually made of Kevlar®. To top it all off, the cable receives a final outer-jacket coating of PVC, which helps to seal out moisture.

For the finished cable to transmit data signals, it needs to be connected to the two other main components of a fiber optic system. The first of these is the optical transmitter, a device which converts electrical and analog signals into either On-Off or Linear modulating light signals, then releases that data into the fiber optic cable. The cable then relays the data emitted by the optical transmitter to the optical receiver, which accepts the light signal and reformats the data into its original form.

Fiber optic cabling has advantages over standard copper coaxial cables, in that it can transmit larger quantities of data with far less loss. It can maintain signals over long distances, carries little risk of corrosion, and is virtually free from interference.


To view a wide array of fiber optic cables and other fiber optic products that can take your telecommunications network to a whole new level, visit us at CableOrganizer®.


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