Uses of Fiber Optic

Fiber optic cables or fiber cables can be used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. Although lc fibers can be made out of either transparent plastic (POF = plastic optical fibers) or glass, the fibers used in long-distance telecommunications applications are always glass, because of the lower optical absorption. The light transmitted through the fiber is confined due to total internal reflection within the material. This is an important property that eliminates signal crosstalk between fibers within the cable and allows the routing of the cable with twists and turns. In telecommunications applications, the light used is typically infrared light, at wavelengths near to the minimum absorption wavelength of the fiber in use.

Fibers are generally used in pairs, with one fiber of the pair carrying a signal in each direction, however bidirectional communications is possible over one strand by using two different wavelengths (colors) and appropriate coupling/splitting devices such as fiber optic tester,fiber optic light source,fiber cables,lc fiber,fiber patch cables.

Modern fiber cables can contain up to a thousand fibers in a single cable, so the performance of optical networks easily accommodate even today's demands for bandwidth on a point-to-point basis. However, unused point-to-point potential bandwidth does not translate to operating profits, and it is estimated that no more than 1% of the lc fiber cable buried in recent years is actually 'lit'.

Modern fiber cables come in a wide variety of sheathings and armor, designed for applications such as direct burial in trenches, installation in conduit, lashing to aerial telephone poles, submarine installation, or insertion in paved streets. In recent years the cost of small fiber-count pole mounted cables has greatly decreased due to the high Japanese and South Korean demand for Fiber to the Home (FTTH) installations.

There two major types of fiber optic cable:

• Single-mode: uses a specific light wavelength. The cable's core diameter is 8 to 10 microns. Single-mode fiber is often used for intercity telephone trunks and video applications.
• Mulit-mode: uses a large number of frequencies (or modes). The cable's core is larger than that of single-mode fiber. Multimode fiber is the type usually specified for LANs and WANs.

Advantages of Fiber Cables over wires

• Low loss of signal (typically less than 0.3 dB/km), so repeater-less transmission over long distances is possible
• Large data-carrying capacity (thousands of times greater, reaching speeds of up to 1.6 Tb/s in field deployed systems and up to 10 Tb/s in lab systems respectively)
• Immunity to electromagnetic interference, including nuclear electromagnetic pulses (but can be damaged by alpha and beta radiation)
• No electromagnetic radiation; difficult to eavesdrop
• High electrical resistance, so safe to use near high-voltage equipment or between areas with different earth potentials
• Low weight
• Signals contain very little power
• No crosstalk between cables
• No sparks (e.g. in automobile applications)

Disadvantages of Fiber Cables compared to wires

• Higher cost
• Need for more expensive optical transmitters and receivers
• More difficult and expensive to splice than wires
• At higher optical powers, is susceptible to "fiber fuse" wherein a bit too much light meeting with an imperfection can destroy several metres per second. A "Fiber fuse" protection device at the transmitter can break the circuit to prevent damage, if the extreme conditions for this are deemed possible.
• Cannot carry electrical power to operate terminal devices. However, current telecommunication trends greatly reduce this concern: availability of cell phones and wireless PDAs; the routine inclusion of back-up batteries in communication devices; lack of real interest in hybrid metal-fiber cables; and increased use of fiber-based intermediate systems.

Almost all these disadvantages have been surmounted or bypassed in contemporary telecommunications usage, and communication systems are now unthinkable without fiber optics. Their cost is much more economic than old coaxial cables because the transmitters and receivers (laser and photodiodes) turn out cheaper than electric circuitry as their capacity is much superior. The cost of regeneration in electrical long distance transmission systems is completely impractical for modern communications for example fiber optic tester,fiber optic light source,fiber cables,lc fiber,fiber patch cables.

Fiber Optic News

Telephone service was restored across Montana's Hi-line early Wednesday evening after a cut fiber optic phone line between Fort Benton and Carter was repaired, a Qwest spokeswoman said.