In a
fiber optic cable
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. The optical fiber elements are typically individually coated with ...
, a buffer is one type of component used to encapsulate one or more
optical fiber
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass ( silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a mea ...
s for the purpose of providing such functions as mechanical isolation, protection from physical damage and fiber identification.
The buffer may take the form of a miniature conduit, contained within the cable and called a "loose buffer", or "loose buffer tube". A loose buffer may contain more than one fiber, and sometimes contains a lubricating
gel
A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still dif ...
. A "tight buffer" consists of a
polymer
A polymer (; Greek '' poly-'', "many" + ''-mer'', "part")
is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...
coating in intimate contact with the primary coating applied to the fiber during manufacture.
Buffer application methods include spraying, dipping, extrusion and electrostatic methods. Materials used to create buffers can include
fluoropolymers such as
polyvinylidene fluoride
Polyvinylidene fluoride or polyvinylidene difluoride (PVDF) is a highly non-reactive thermoplastic fluoropolymer produced by the polymerization of vinylidene difluoride.
PVDF is a specialty plastic used in applications requiring the highest pur ...
(Kynar),
polytetrafluoroethylene (Teflon), or
polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from ...
.
See also
*
Core (optical fiber)
The core of a conventional optical fiber is the part of the fiber that guides the light. It is a cylinder of glass or plastic that runs along the fiber's length. The core is surrounded by a medium with a lower index of refraction, typically a ...
*
Cladding (optical fiber)
Cladding in optical fibers is one or more layers of materials of lower refractive index, in intimate contact with a core material of higher refractive index. The cladding causes light to be confined to the core of the fiber by total internal ref ...
References
Fiber optics
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