How works the optical fiber?

Normally you hear things on optical fiber cables when people speak of the telephone systems or the systems of television by cable or Internet. The lines of optical fiber are as fine glass threads pure optical as the human hair, and that transport digital information on long distances. This technology also is used in the medicine and engineering in several of its forms. We will see in this tutorial one on the optical fiber, as these small fiber threads transmit the light and as they are created.
Composition of the optical fiber
The optical fibers are long and very fine threads of pure glass, that is grouped in sets or groups, and that are called optical cables, and that transmit signals of light to long distances. If sights of fence one of these optical fibers, you will be able to see that one is made up of the following parts:

• Nucleus - It is the center of the fiber formed by a fine glass where the light travels.
• Coating - It is the optical devices that surrounds to the nucleus and that reflects the light of return to the nucleus.
• External cover - It is the plastic cover that protects the fiber of possible damages and the humidity.

Hundreds of thousands of these optical fibers are grouped in greater optical cables, than they are protected as well by an external cover called jacket. The optical fibers can come in two ways.

• Fibers monkey-way
• Fibers multi-way

The fibers monkey-way have small nuclei, with about nine microns of diameter. They transmit the light laser with a wavelength among 1300 to 1550 nanometers. The fibers multi-way have greater nuclei with a diameter of about 63 microns and one transmission of light among 850 to 1300 nanometers.
How is transmitted the light in an optical fiber?
Supón that you want to illuminate with a lantern a long and straight corridor. There would not be any problem, since it is only necessary to point the ray of light by the corridor and this light will travel in line straight at the end of the corridor. What happens if the corridor has some turn or doblez? You could put a mirror in the curve to reflect the light ray so that it illuminated the corner. That it happens if the corridor has many corners? You would have to put several mirrors in the walls and to calculate the deflections that it would have to make the ray of light by all the full way of corners. This is exactly what it happens with the optical fiber.
The light in an optical fiber travels continuously by the nucleus (corridor) bouncing with the coating (mirrors in the walls), which is called total internal reflection. The coating does not absorb anything of light of the nucleus, the light can travel by long distances. Nevertheless, some of the light signals can be degraded within the fiber, mainly by the impurities of the glass. The extension of this degradation depends on the purity of the glass and the wavelength of the transmitted light.
The optical fiber system
Basically the optical fiber system is made up of a transmitter, the optical fiber in if, an optical regenerator and an optical receiver.
The transmitter - It is physically near the optical fiber and can even have lenses to focus the light in the fiber.
Optical regenerator - Since it has commented, signals when the light within the fiber is transmitted, especially in long distances can be lost. One or for this reason, more regenerative optician is put throughout the cable to increase the signal of degraded light.
An optical receiver - the signal of incoming digital light Receives to decode, it and sends the electrical signal to the other users, who can be computers, television or system of telephones. The receiver uses a photo cell or photo diode to detect the light.
Advantages of the optical fiber
Why the optical fibers have revolutionized the telecommunications? Comparing it with conventional copper cables, we can take to consider these advantages:

• Less expensive - Several kilometers of optical cable can be cheaper than their copper cable equivalent. This saves money to the suppliers of services and their users.
• But fine - the optical fibers use diameters smaller than other cables, not occupying as much space.
• Greater capacity to transport data - To the being finer cables, amount of fibers in a single optical cable can be grouped major. This allows but to amount of telephone lines or channels in a single cable, increasing its capacity.
• Smaller degradation of the signal - the degradation of the signal is minor who in copper cables.
• Signals of light - Unlike the electrical signals in copper cables, the signals of light of a fiber, do not interfere with the other fibers in the same cable. This is translated in clearer conversations by telephone and one better reception of the television by cable, for example.
• DS - the optical fibers are ideal to take digital information, which is very useful in networks of computers.
• More flexible use - To the power to transmit and to receive light of a flexible form, can be given many uses him with totally different elements, like digital cameras, medicine mechanical engineering, security, etc.

By all this, in many cases the optical fiber is moving to another type of cables in many industries, mainly in the telecommunications and the networks of computers. Like anecdote, when you have possibly spoken on the telephone with somebody to much distance, perhaps you have heard an echo. In the new optical fiber systems east problem has been corrected.