Page 85 - 2020 Interconnect Innovations eBook

typical diameter of 50–62.5 microns. Multimode fiber bandwidth is limited by its light mode, while single-mode fiber bandwidth is theoretically unlimited, because it allows only one light mode to pass through at a time. Single-mode cables transmit 1,310nm or 1,550nm and multimode typically transmits 850nm or 1,300nm, both based on allowable optical transmission windows. In addition, the attenuation of multimode fiber is higher than single-mode fiber because of its larger core diameter. Since the fiber core of single-mode cable is narrower, the light that passes through these fiber optic cables is not reflected as much, which reduces attenuation.
Transmission Distance: Single-mode cables are a designed to transmit data over long distances via a single strand of glass fiber with one mode of propagation. Although single-mode fiber transmits data at a higher bandwidth and at distances of up to 50 times farther than multimode fiber, it requires a light source with a narrow spectral width.
Multimode cables are optimized for shorter and medium distances, such as local-area networks (LANs) and can achieve speeds up to 100GbE. However, in cable runs longer than 900 meters, the multiple cable pats can cause distortion at the receiving end, resulting in partial data transmission and reception.
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» An M29504/4 and /5 POF termini pair from XiOptics.
Durability: Fiber optic cabling has a reputation for being fragile and difficult to install. But in reality, fiber optic cabling is incredibly strong and flexible. The failure point for optical media can be less than a 0.1” bend radius. Most fiber optic cables are manufactured to withstand installation stresses, and especially the pulling strength requirements, by including Kevlar aramid strength members designed to provide a soft jacket and padding and protect the optical fibers. External jackets are also available in a wide range of rugged polymers. Fiber optic cable can be installed in harsh environments where it is immersed in water, buried in salty or sandy soil, hung in the air, and used near high- voltage and high EMI equipment. It is resistant to twisting, vibration, bending, crushing, impact forces, and extreme temperature swings and is qualified for use in commercial aviation applications.
Moreover, while traditional electrical connectors require additional plating, such as brass nickel or more expensive gold for corrosion resistance, fiber optic connectors require no additional plating. Connector housings are most commonly ceramic or stainless steel, depending on the installation conditions, and clips and locking mechanisms are often made from durable beryllium copper.
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» An M38999 connector populated with MIL-T-29504 fiber optic termini from XiOptics.