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, like waveguides , can have various transmission modes. The fibers used for long-distance communication are known as single mode fibers , as they have only one strong propagation mode.
This results in superior performance compared to other, multi-mode fibers , where light transmitted in the different modes arrives at different times, resulting in dispersion of the transmitted signal. Typical single mode fibers can sustain transmission distances of 80 to km between regenerations of the signal, whereas most multi-mode fibers have a maximum transmission distance of to metres.
Note that single mode equipment is generally more expensive than multi-mode equipment. Because of the remarkably low loss and excellent linearity and dispersion behavior of single-mode optical fiber, data rates of up to 40 gigabits per second are possible in real-world use on a single wavelength.
Wavelength division multiplexing can then be used to allow many wavelengths to be used at once on a single fiber, allowing a single fiber to bear an aggregate bandwidth measured in terabits per second. 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.
Modern 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.
The light forms an electromagnetic carrier wave that is modulated to carry information. First developed in the s, fiber-optic communication systems have revolutionized the telecommunications industry and have helped with the advent of the Information Age. Early systems had short range but later ones used fibers that are more transparent.
Since the light does not leak out of the fiber, the light can go a long distance before the signal gets too weak. This is used to send telephone and internet signals within and between cities. Because of its advantages over electrical transmission, optical fibers have largely replaced copper wire communications in core networks in the developed world. Most optical communication systems have electrical connections.
An electric signal controls a transmitter. The transmitter converts the electric signal to a light signal and sends it through the fiber to the receiver. The receiver converts the light signal back to an electric signal.
Fiber is sometimes used for shorter links too, such as to carry the sound signals between a compact disc player and a stereo receiver. The fibers used for these short links are often made of plastic which is less transparent. Optical fibers can be used as sensors. Special fibers are used for this, that change how they pass light through when there is a change around the fiber.
Sensors like this can be used to detect changes in temperature , pressure , and other things. These sensors are useful because they are small and do not need any electricity at the place where the sensing happens. These fibers are also used to carry light for humans to see.
This is sometimes used for decoration, like fiber-optic Christmas trees. Sometimes it is used for lighting, when it is convenient to have the light bulb someplace other than where the light needs to be. This is sometimes used in signs and art for special effects. A bundle of fibers can be used to make a device called an endoscope or a fiberscope. Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots.
Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Prev NEXT. If you look closely at a single optical fiber, you will see that it has the following parts: Advertisement. Core - Thin glass center of the fiber where the light travels Cladding - Outer optical material surrounding the core that reflects the light back into the core Buffer coating - Plastic coating that protects the fiber from damage and moisture.
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