It is very important for beginners to know these terms when working with fibre optic cables. Friends who are already working in fibre optic cable will be well familiar with all these terms. This article covers most of the commonly used terms and their definitions in the fibre optic cable field.

A fibre optic is a thin strand of highly transparent glass or plastic that guides light. It is used as a medium to carry information in the form of light from one point to another. Due to this Fibre Optic Cable, today communication has become so simple and fast all over the world.

Terms used in Fibre Optic Cable

It is very important for those working in the field related to fibre optic cables to be thoroughly familiar with all the terms given below. These are important and necessary conditions without which working in fibre optic cable is exactly like a person running without legs. Now I am going to discuss those important and necessary terms below:

Patch panels

Patch panels provides a centralised location for patching or provide connectivity of fibres, testing points, monitoring and restoring of Fibre optics cables. 

Connector 

Connectors are a non-permanent device which provide connectivity between two fibres or fibres to equipment where they are expected to be disconnected occasionally for testing or rerouting. It also provides protection to both fibres.

Ferrule

It is a tube like structure which is connected to the connector, it holds a fibre for alignment, we can say that it is usually part of a connector.

SC connector 

SC Stands for Single Coupling. It is a Square shaped snap-in connector that latches with a simple push-pull. The SC connector has the advantage (over ST) of being duplexed into a single connector clip with both transmit/receive fibres.

ST Connector

ST Stands for Straight Tip. The ST connector is spring-loaded bayonet mount and have a long cylindrical ferrule to hold the fibre.

LC Connector

LC stands for Latched Connector and it’s interconnect is based upon the RJ-45 telephone interface. The LC Connector uses Zirconium ceramic ferrules in a free-floating and pull proof design.

MU Connector 

The MU stands for Miniature Unit fibre-optic connector, which features compact size, high packaging density, and high performance and a simple push-pull design. The MU connector ferrules are half the size of the standard FC, SC connectors and are excellent for high-density installations.

Short form Terms         Full forms            

PC Connector              Physical Contact Connector

FPC Connector            Flat Physical Contact Connector

APC Connector            Angled Physical Contact Connector

SPC Connector            Super Physical Contact Connector

UPC Connector           Ultra Physical Contact Connector

Splice enclosures 

The point where one fibre optic cable drum ends and a second fibre optic cable drum is used to continue a long distance network, where the cables are joined, sealed and buried in the ground Is or is kept in an underground chamber or hung from a pole. That is called the Splice enclosures.

Splice panels

In Splice panels individual fibres from cables are connected  to pigtails. From this point, further extension and diversion of fibre optic becomes easy.

Mechanical Splice 

A splice where the fibres are aligned by mechanical or in other word we can say that splicing of fibre optic without splicing machine.  

Fusion Splice 

An instrument that splices fibres by fusing them, typically by electrical arc. A splice is done by fusing two fibres together.

Optical Power Meter  

This instrument used to measures the optical power from the end of a fibre.

Laser Source

An instrument that uses a laser or LED to send an optical signal into fibre for testing loss of the fibre.

Optical Loss Test Set (OLTS) 

A measurement instrument for optical loss that includes both a power meter and laser source.

Reference Test Cables 

A Short and single fibre cable with connectors on both ends, used to test unknown fibre optic cables. 

Mating Adapter 

Also called couplers, allow two cables with connectors to mate.

Optical Microscope 

Often used to inspect the end surface of a connector for dirt.

Attenuation

The reduction or losses in optical power as it passes along a fibre optic cable, usually expressed in decibels (dB). 

Bandwidth

The range of signal frequencies or bit rate within which a fibre optic link or network will operate.

Chromatic Dispersion

A property of optical fibre due to which different wavelengths travel at different speeds and arrive at different times, resulting in spreading of a pulse in an optical wave guide.

Decibels (dB)

A unit of measurement for optical power, which indicates relative power. Meaning of -10 dB reduction in optical power is by 10 times.

dBm - dB milliWatt

It represent the signal strength. 0 dBm is 1 mW of power into a power meter. Optical power referenced to 1 milliwatt  

Nanometer (nm) 

A unit of measure used to measure the wavelength of light (meaning one-billionth of a meter). 

Optical Loss

The amount of optical power lost during transmission of through fibre, splices, couplers, etc. expressed in dB.

Optical Power

It is measured in dBm or decibels referenced to one milliwatt of power. While loss of optical power is a relative reading, optical power is an absolute measurement, referenced to standards. Absolute power is measured to test transmitters or receivers and relative power to test loss.

Back Reflection

Light reflected from the cleaved or polished end of a fibre caused by the difference of refractive indices of air and glass. 

Power Budget

It is the total amount of power lost in the optical link. It is calculated as per length of link. It is often used in terms of the maximum amount of optical loss that can be tolerated by a given link.

Polarization Mode Dispersion

The spreading of a pulse in an optical wave guide by virtue of different light paths lengths is called Modal dispersion.

Refractive Index

A measure of the speed of light in a material, a property of optical materials that relates to the velocity of light in the material.

Scattering

The change of direction of light after striking small particles that causes loss in optical fibres and is used to make measurements by an OTDR.

Wavelength

A term for the colour of light, usually expressed in nanometres (nm) or microns (m). Fibre Optic is generally used in the infrared region where light is invisible to the human eye.

Units, Power Prefixes

You can also read:

# Ethernet Cable - How to Choose the Best One

# Bandwidth : The Concept of Bandwidth

# What is the best fiber for FTTH?

# Parameters Of Optical Fiber

# Fundamentals of Optical Fibers and Communication

# Parameter of Optical Splitter Loss

# How to place OFC Joint Box in Manholes?

# Why needed cladding in optical fiber?

# FTTH Network Testing During Construction

# Dark Fiber : Why called Dark Fiber?

# How OTDR calculate the optical length?

# How to understand the OTDR trace?

# What is Backscatter coefficient K?

# Dispersion Compensation Module (DCM)

# Important Steps for FOC Splicing

# Multi-mode Optical Fiber

# How many types of Single mode Fiber?

Conclusion

Friends, I hope that you all liked this article Terms used in Fibre Optic Cable. Apart from this, with the help of the link given above, you can get information as per your need. If you liked the article then share it with others also.