There are many types of fiber optic cable used to supply data to mobile phones, computers and TVs, each handling light in a different way, and each made for a different application. There are two main types of optical fiber cable, multimode and single mode, which use either several beams of light or a single beam at once. Simplex cables use only one or two optical fibers and Kevlar protection. Tightpack cables contain many optical fibers, but the fibers are not individually terminated. Loose tube cables include a water blocking gel and are used outdoor or are buried underground.
Multimode and single mode are the two main types of optical fiber cable, though the terms do not refer so much to the cable design as to how the fibers interact with light. The multimode version sends out many different light beams at once, and each is sent at a different angle so the beams cannot interact with each other, eliminating the chance of interference. These types of optical fiber cable can only be used for short distances; otherwise, the light beams begin to interfere with on another. Single mode optical fibers send only one beam of light at a time, making them ideal for long distances, because there are not multiple light beams to cause interference.
While a multi-mode optical fiber is cheaper than a single-mode fiber, it is only effective at supplying power to short distances, around 1,968 feet (600 meters). This is because of the different light rays working at once. If the cable is used for longer distances, the light rays begin either to conflict or disperse, meaning that power is inefficiently transferred or will not reach the target destination.
Simplex cables are simplx fiber optic cables that are used for backplanes and patch cord purposes. The outside is reinforced with Kevlar to keep the optical fibers from wearing down as a result of outside stress. Inside, there are only one or two fibers, which make it good for applications for which limited energy is needed.
Tightpack cables are similar to simplex but include many more fibers. The fibers are paired up and jacketed, as with the simplex cables, but there are many pairs, not just one. A major difference, aside from fiber number, is that the fibers are not individually terminated or protected, so there must be a termination unit connected to these types of optical fiber cable. These cables are used mostly for dry conduit runs over short distances.
Loose-tube cable does not use protection or jacketing for their internal fibers, but have another way of keeping the fibers safe. The insulation is filled with a water-blocking gel that is able to keep water from leaking into the cable and also keeps the fibers safe by adding durability to the inside of the cable. These cables are often used outdoor, either in the air or buried underground.