In a fiber optic cable, a buffer is one type of component used to encapsulate one or more optical fibers 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 "tight buffer" consists of a polymer 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 (Kynar), polytetrafluoroethylene (Teflon), or polyurethane. [1]
A transmission medium is a system or substance that can mediate the propagation of signals for the purposes of telecommunication. Signals are typically imposed on a wave of some kind suitable for the chosen medium. For example, data can modulate sound, and a transmission medium for sounds may be air, but solids and liquids may also act as the transmission medium. Vacuum or air constitutes a good transmission medium for electromagnetic waves such as light and radio waves. While material substance is not required for electromagnetic waves to propagate, such waves are usually affected by the transmission media they pass through, for instance, by absorption or reflection or refraction at the interfaces between media. Technical devices can therefore be employed to transmit or guide waves. Thus, an optical fiber or a copper cable is used as transmission media.
In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths of laser light. This technique enables bidirectional communications over a single strand of fiber, also called wavelength-division duplexing, as well as multiplication of capacity.
A fiberscope is a flexible optical fiber bundle with an eyepiece on one end and a lens on the other that is used to examine and inspect small, difficult-to-reach places such as the insides of machines, locks, and the human body.
Hybrid fiber-coaxial (HFC) is a telecommunications industry term for a broadband network that combines optical fiber and coaxial cable. It has been commonly employed globally by cable television operators since the early 1990s.
A passive optical network (PON) is a fiber-optic telecommunications technology for delivering broadband network access to end-customers. Its architecture implements a point-to-multipoint topology in which a single optical fiber serves multiple endpoints by using unpowered (passive) fiber optic splitters to divide the fiber bandwidth among the endpoints. Passive optical networks are often referred to as the last mile between an Internet service provider (ISP) and its customers.
An optical fiber connector joins optical fibers, and enables quicker connection and disconnection than splicing. The connectors mechanically couple and align the cores of fibers so light can pass. Better connectors lose very little light due to reflection or misalignment of the fibers. In all, about 100 different types of fiber optic connectors have been introduced to the market.
A patch cable, patch cord or patch lead is an electrical or optical cable used to connect one electronic or optical device to another for signal routing. Devices of different types are connected with patch cords.
Breakout-style fiberoptic cable, is an optical fiber cable containing several jacketed simplex optical fibers packaged together inside an outer jacket. This differs from distribution-style cable, in which tight-buffered fibers are bundled together, with only the outer cable jacket of the cable protecting them. The design of breakout-style cable adds strength for ruggedized drops, however the cable is larger and more expensive than distribution-style cable. Breakout cable is suitable for short riser and plenum applications and also for use in conduits, where a very simple cable run is planned to avoid the use of any splicebox or spliced fiber pigtails.
An optical fiber 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 means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss; in addition, fibers are immune to electromagnetic interference, a problem from which metal wires suffer. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are also used for a variety of other applications, some of them being fiber optic sensors and fiber lasers.
Fiber to the x or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber optic cables are able to carry much more data than copper cables, especially over long distances, copper telephone networks built in the 20th century are being replaced by fiber.
Hitachi Cable, Ltd. was established in 1956 as a manufacturer of electric wire and cable for power distribution. The company, based in Tokyo, Japan, was formed from Hitachi Densen Works, the Hitachi Works spin-off previously known as Densen Works.
Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of infrared light through an optical fiber. The light is a form of carrier wave that is modulated to carry information. Fiber is preferred over electrical cabling when high bandwidth, long distance, or immunity to electromagnetic interference is required. This type of communication can transmit voice, video, and telemetry through local area networks or across long distances.
An optical ground wire is a type of cable that is used in overhead power lines. Such cable combines the functions of grounding and communications. An OPGW cable contains a tubular structure with one or more optical fibers in it, surrounded by layers of steel and aluminum wire. The OPGW cable is run between the tops of high-voltage electricity pylons. The conductive part of the cable serves to bond adjacent towers to earth ground, and shields the high-voltage conductors from lightning strikes. The optical fibers within the cable can be used for high-speed transmission of data, either for the electrical utility's own purposes of protection and control of the transmission line, for the utility's own voice and data communication, or may be leased or sold to third parties to serve as a high-speed fiber interconnection between cities.
Hydrogen darkening is a physical degradation of the optical properties of glass. Free hydrogen atoms are able to bind to the SiO2 silica glass compound forming hydroxyl (OH)—a chemical compound that interferes with the passage of light through the glass.
Sumitomo Electric Industries, Ltd. is a manufacturer of electric wire and optical fiber cables. Its headquarters are in Chūō-ku, Osaka, Japan. The company's shares are listed in the first section of the Tokyo, Nagoya Stock Exchanges, and the Fukuoka Stock Exchange. In the period ending March 2021, the company reported consolidated sales of US$26,5 billion.
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 plastic layers and contained in a protective tube suitable for the environment where the cable is used. Different types of cable are used for different applications, for example, long distance telecommunication, or providing a high-speed data connection between different parts of a building.
Fiber cable termination is the addition of connectors to each optical fiber in a cable. The fibers need to have connectors fitted before they can attach to other equipment. Two common solutions for fiber cable termination are pigtails and fanout kits or breakout kits.
Paper chemicals designate a group of chemicals that are used for paper manufacturing, or modify the properties of paper. These chemicals can be used to alter the paper in many ways, including changing its color and brightness, or by increasing its strength and resistance to water.
The Telecommunications Industry Association's TIA-598-C Optical Fiber Cable Color Coding is an American National Standard that provides all necessary information for color-coding optical fiber cables in a uniform manner. It defines identification schemes for fibers, buffered fibers, fiber units, and groups of fiber units within outside plant and premises optical fiber cables. This standard allows for fiber units to be identified by means of a printed legend. This method can be used for identification of fiber ribbons and fiber subunits. The legend will contain a corresponding printed numerical position number and/or color for use in identification.
All-dielectric self-supporting (ADSS) cable is a type of optical fiber cable that is strong enough to support itself between structures without using conductive metal elements. It is used by electrical utility companies as a communications medium, installed along existing overhead transmission lines and often sharing the same support structures as the electrical conductors.