Faster connections

How to ensure high quality and reliability of fibre optic components

By Claire Marchand

Fibre optic lines have revolutionized communications, from long-distance phone calls to cable TV and Internet. Business and industry have used fibre optic technology for years to move large amounts of data quickly. Fibre-based communication is expected to grow tremendously in years to come.

TOSLINK fibre optic
A TOSLINK (Toshiba Link) fibre optic audio cable (Photo: Hustvedt in Wikipedia)

Coming home

In recent years, Fibre-to-the-Home (FTTH) has brought the technology to many households. In FTTH, fibre optic cables are installed from the telephone exchange to deliver communications such as broadband, digital TV and telephone to private homes.

Fibre optic cables offer much faster speeds and much higher bandwidth than copper wires. The multimedia and telecommunications sectors rely more and more on fibre optics for instantaneous data transmission.

Complex components

Since the fibre system is much more complicated than the former copper wired system, components needed for these optical networks are also extremely sophisticated.

Typical fibre optic components include transceivers, optical amplifiers, couplers/splitters, WDM (wavelength-division multiplexing) multiplexers and demultiplexers, filters, isolators, circulators, attenuators, optical switches, wavelength converters and various function modules. The entire range of components can be classified in one of two ways: passive or active type. Passive fibre optic components work without external power, while active fibre optic components need external power to operate.

Fibre optic sensors

Fibre optic sensors (FOSs) use optical fibre either as the sensing element – intrinsic sensors – or to relay signals from a remote sensor to the electronics that process the signals – extrinsic sensors.

FOSs are immune to electromagnetic interference and do not conduct electricity, so they can be used in places where there is high voltage or flammable materials such as gases or fuels. FOS can be designed to withstand ultra-high temperatures (1 000 °C) as well as corrosive atmospheres.

Optical fibres used as sensors – intrinsic FOSs – measure strain, temperature, pressure and other quantities by modifying a fibre so that the quantity to be measured changes the intensity, phase, polarization, wavelength or transit time of light in the fibre. Intrinsic FOSs can provide distributed sensing over very large distances.

An extrinsic FOS simply guides the light to a sensing point where the optical signal emerges into another medium within which it is modulated (variation of its intensity, phase, polarization, wavelength, etc.). The light is then collected by the same or a different fibre after it has been modulated by the quantity to be measured and returned to a remote location for processing. (For more on FOSs, see article in the November 2014 issue of e-tech)

IEC International Standards for fibre optics

Manufacturers and suppliers of optical fibres and their components can rely on the IEC to provide the tools necessary to ensure the quality and reliability of their products.

IEC Technical Committee (TC) 86: Fibre optics, its three Subcommittees (SCs) and their Working Groups(WGs) are central to the development of the entire sector and all related industries as they prepare Standards, specifications and technical reports for fibre optic-based systems, subsystems, modules, devices and components.

A Working Group of IEC SC 86C: Fibre optic systems and active devices, is preparing and maintaining International Standards and specifications for FOS.

High quality components

To ensure the quality and reliability of the components used in optical fibre assemblies, manufacturers and suppliers have a powerful tool at their disposal. IECQ, the IEC Quality Assessment System for Electronic Components, provides certification at the international level for a wide variety of electronic components, including those found in fibre optic systems.

IECQ offers immediate international recognition. One test and one certificate issued in one country means acceptance on a global basis, even in countries that are not IECQ Members.

Reducing the use of hazardous substances

Nowadays, electronic component manufacturers who have had their products tested and certified by IECQ also request IECQ HSPM (Hazardous Substance Process Management) certification to demonstrate that their products are produced under controlled conditions to provide assurance that they meet hazardous-substance-free specific local, national and international requirements.

This is of particular importance for fibre optics as networks increasingly extend across borders. For this reason they have to comply with different national regulations that may restrict or prohibit the use of such substances in components.

The IECQ System provides all players in the ever expanding fibre optic market with the certainty of using electronic components that meet the strictest requirements and are of the highest quality.

For more information on IECQ: www.iecq.org

Gallery
fibre optic cable Fibre optic cables
fibre optic pressure sensor Fibre optic pressure sensor (Photo:FocusTek)
TOSLINK fibre optic A TOSLINK (Toshiba Link) fibre optic audio cable (Photo: Hustvedt in Wikipedia)