Kevlar® is the registered trademark for the strong synthetic material or yellow 'hair' used as a protective outer sheath for the glass fiber core it protects. Its high tensile strength protects the cable from damage when being pulled. Structurally, a fiber cable comprises the core, cladding, coating, strength member, and outer jacket. The fiber jacket protects against moisture, UV exposure, chemicals, and mechanical abrasion. Larger core sizes allow a larger amount of light, or a larger beam diameter, to enter the fiber. The numerical aperture. A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. Many factors influence the design of fiber-optic cables.
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