Fiber optics deals with the transmission of information by passing light through flexible optical fibers. Electrical impulses are converted to light, which is then transmitted through an optical cable. The light signal is then converted into electrical impulses at the destination.
Optical fibers are strands of optically pure glass, thin as hair. They are usually located in bundles known as optical cables, which are used to transmit light signals. Fibers allow you to transmit signals through them with minimal loss and without electromagnetic interference. This makes it an ideal mode for transmitting information over long distances and with higher bandwidth.
Optical fiber consists of the following parts.
1. The core is a thin glass in the center of the fiber in which the light passes.
2. Facing - coating of optical material, which prevails over light from the exit from the core.
3. Buffer coating. This is a plastic coating that protects the fibers from damage and moisture.
Packs are usually covered with a jacket.
There are two types of fibers. The first is multimode. It has a larger core diameter (2.5 * 10-3 inches) and transmits infrared radiation with a wavelength of 850 nm to 1300 nm from light-emitting diodes. Another type is single mode fiber. Its core diameter is 3.5 * 10-4 inches and transmits infrared light with a wavelength from 1300 to 1550 nm.
The light in the cable moves inside the core, constantly bouncing off the shell according to a principle known as total internal refraction. The light wave travels long distances, since the light is not absorbed, but is reflected back into the core through the principle mentioned above.
However, some of these signals are getting worse. It depends on the impurities present in the glass and the wavelength of the transmitted light. Light with a wavelength of 850 nm is characterized by a degradation of 60-65% / km, while a wavelength of 1300 nm is 55-60% / km, and a wavelength of 1550 nm is less than 45% / km. Some high-quality cables show very little signal degradation, no more than 8% / km at 1550 nm.
To communicate with the use of this system, we need a fiber optics relay system, which consists of the following.
1. Transmitter. It generates light signals in a specific code and is usually placed near the optical cable. It produces light with a wavelength of 850 nm, 1300 nm and 1550 nm.
2. Optical cable. Conducts light signals at a distance.
3. Optical regenerator - usually necessary to amplify signals that are transmitted at a very long distance. It consists of fibers that have been doped. The doped part is served by a laser. When deviating signals reach the doped region, the molecules in this region emit another stronger signal, which resembles a degraded light signal.
4. Optical receiver - it receives digital light signals, decodes them into the appropriate electrical signal, which is then sent to the desired machine.
There are several benefits that come with the use of optical cables.
1. It is cheaper.
2. It has a higher bandwidth.
3. Reduces signal degradation.
4. Can transmit digital signals.
5. It is light weight.
6. Low power required for signal transmission.
Currently, fiber optics are the best way to not wirelessly transfer data, especially in this digital age.
