The four major components of the fiber optic patch cord:

  • Jacket – The jacket is the external covering of the fiber optic cable. While it offers protection, its primary purpose is not to provide strength. Essentially, the jacket holds all components together: the aramid strength members and buffered fiber, which encompass the optic fiber.


  • Aramid strength members – Aramid yarns are strong, heat-resistant fibers. In the fiber optic cable assembly, the aramid strength members provide tensile strength from the connector and throughout the cable. For example, during the manufacturing process, as you pull the cable onto the connector, the aramid strength members help to assure the cable and the glass optic fiber won’t break. (Note that aramid strength members are often referred to as Kevlar®, which is a trademarked name for a particular brand of aramid yarn.)


  • Buffer coating on the fiber – The glass optic fiber is manufactured with a protective (buffer) coating against damage. Depending on the patch cord’s application, the buffer coating can be a variety of different materials that will offer, for example, resistance to high-temperatures or fire resistance. The buffer also protects the acrylate-coated fiber as it is extruded into the jacket as well as acting as a “seal,” if you will, of that acrylate-coated fiber before splicing or connectorization.


  • Optic fiber – Manufactured from glass or plastic, the optic fiber is an optical waveguide comprised of a light-carrying core and cladding, which traps light in the core. Fiber optic communication systems use either single mode or multimode types.



READ THE FULL BLOG ARTICLE HERE: Introduction to Fiber Optic Cable Assembly Manufacturing Part 1: Components of the fiber optic patch cord and optic fiber geometry



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