Fiber optics: brief introduction to the data transfer system using pulses of light

Fiber optics is becoming more and more common in Internet connections, but do we really know a little about how it works and what advantages and disadvantages it has?

Possibly, many of you already have a fiber optic-based internet connection at home. The copper pair gives way to fiber optics, leaving behind its technical limitations and giving way to the future.

Optical fiber has drawbacks, such as its more delicate handling, which makes its assembly and maintenance more difficult. This is based on light, specifically in the manipulation of light impulses, which implies that it is more susceptible to variations in the conductor

In this article, we will see the structure of a fiber optic cable and what are the components of a fiber installation. This will allow us to see the advantages and disadvantages that it has compared to older systems, such as copper. We will mainly talk about cables and their structure, as well as the types of connections available.

We will also see in a simplified way the most common types of connection. Highlight that there are different fiber optic accessories, but these we will leave it for later.

Elements of a fiber optic cable (from the center to the outside)

1. Dielectric core element: Non-conductive filament of electricity (dielectric) that helps in the consistency of the cables. Not available on all cable types.
2. Moisture drain thread: It conducts the possible humidity to avoid that it stays in the rest of the parts.
3. Fibers: Element through which the information is transmitted, and therefore, the most important part. It can be based on silicon (glass) or heavily processed plastics. The physical processes of reflection and refraction take place within these cables. The material used determines whether it is good for the broadcast or not. Any type of impurity can modify the light beams, causing it not to reach its destination. To generate the strands (microns wide), they are obtained when the glass tubes are exposed to extreme heat and then being extruded, as if they were spaghetti, each strand is obtained.
4. Loose Buffers: Small tube that covers the fibers. Occasionally it may contain a gel that adds darkness to prevent light rays from scattering out of the fiber.
5. Mylar tape: Very thin polyester layer that was initially used for the transmission of PC programs, but has become an insulator.
6. Flame tape: Cover that protects the cable from heat and flames (up to a point)
7. Kevlar synthetic threads: They add consistency and protection to the cable. This material is also quite fire retardant and withstands stretching well.
8. Tear thread: Threads that increases the resistance of the cable
9. Sheath: Cable cover that offers insulation and consistency to the elements inside.

Physical principles of reflection and refraction in fiber optic cables

• Refraction: Change of direction of waves when they pass from one medium to another due to the speed of light.
• Reflection: Change of direction of the wave towards the origin, normally this direction corresponds to the same angle of incidence.

These are the two principles that occur within a fiber optic cable. But there are two types of fibers, which have different types of uses. The two groupings are based on the way light is transmitted within the fiber:

• Single mode: There is only one light inside the fiber. Transmissions of up to 300 kilometers can be given under ideal conditions from a laser light source.
• Multimode: Several beams of light within the fiber. Normally the light source is low intensity IODES, allowing propagation distances of up to 3 kilometers. They are very inexpensive and easy to install.

Types of connectors for fiber optic cables

• FC: For data transmission and telecommunications
• FDDI: Fiber optic networks
• LC and MT-Array: High data density data transmission. Mostly used in servers and storage clusters
• SC and SC Duplex: For data transmission
• ST or BFOC: Building networks and high security systems

All these connectors have simple connection systems or connection rosettes for fiber optics.

Two types of elements are used for the transmission of light in the plates:

• To be: Very powerful and normally used in single mode cables
• LEDs: Economical, low-power and used in multimode

These connection interfaces have the mission of generating the light pulses in binary for communication with a PC. They are generated in this way:

• Light pulse: 1
• Darkness: 0

Advantages of fiber optics

• Controller
• Scalable
• Lightweight, low-corrosion cable
• Low signal loss

Disadvantages of fiber optics

• Connectors, cables, plates, devices, etc., have a high cost for commercial use
• It is very fragile, something that complicates its installation
• Splicing the fiber is very complex, so the installations must be carried out by professionals
• An optical-electrical converter is always needed, since the cost of a complete fiber network would be very high.