What are fibre optic cables?

Fibre optic cables and accessories

Optical fibre cables, better known as fibre optic cables, transmit signals in the form of light.

They are usually made of quartz glass or plastic and are mainly used as patch cables and in the audio sector. The typical cross-section of a fibre optic cable consists of four layers:

Core, the inner core
Cladding, the sheathing of the core
Coating or buffer, a protective coating of the sheath
Jacket, the outer sheath of the cable.

Advantages over copper cables

Fibre optic cables outperform copper cables in almost all performance ranges. They work with a comparatively small core diameter, low signal attenuation, no line resistance and are free from electromagnetic influences - the advantages are extensive:

Fibre optic patch cables allow data transfers at higher transmission rates over longer distances. And all this with a lower weight and longer service life.
Thanks to galvanic isolation, earthing is also not required
The reduced material requirement saves raw materials and resources during production.

Disadvantages compared to copper cables

The main drawback of fibre optic cables compared to copper cables lies in their mechanical properties. Glass fibre is sensitive and can only be bent, kinked or twisted to a limited extent. This means that it can only be used to a limited extent on angled cable routes. Another disadvantage of fibre optic cables becomes apparent during installation: their assembly is more complex than that of copper cables.

Fibre optic cable

Special fibre optic cables are available depending on the area of application: Outdoor cables are laid in the ground or in pipe systems. They are moisture-resistant and more stable than indoor cables. They can easily withstand rodent bites, for example. Breakout cables are multi-channel cables. They consist of several fully-fledged individual cables. They split at the connection and can be fitted with different plugs to suit the application. This allows several cables to be laid quickly and easily.

Simplex and duplex cable (directional dependency)

Fibre optic cables are communication channels through which information is transported. Such channels differ in their so-called "directionality": simplex defines the transfer of information in one direction, duplex enables simultaneous transmission in both directions. Simplex cables are therefore only suitable for data transmission in one direction at the same time. They consist of one fibre and are fitted with simplex connectors at both ends. Duplex cables allow operation on two channels thanks to their (at least) two fibres. This means that data can be sent and received simultaneously. Duplex cables are usually supplied pre-assembled with duplex connectors.

Multimode/Singlemode/Monomode

Another distinguishing feature of fibre optic cables is the size of the fibre core. At nine micrometres, the fibre core of single-mode cables (OS1 and OS2 category) is so small that it allows the propagation of exactly one mode. A mode can be described as a light oscillation. In larger multimode fibres (category OM1, OM2, OM3, OM4, OM5) up to 62.5 micrometres, several modes can propagate. Handling is technically less complex. However, the transmitted signal is distorted with increasing transmission distance. This is why multimode fibres are only used over short distances of less than one kilometre.

OM5 the current standard for fibre optic cables

OM5 is a further development of OM4 and is designed to meet the growing needs of modern data centres and the requirements of new data transmission protocols.

OM5 is often referred to as broadband multimode fibre because it is specifically optimised for short distances and high speeds, typically in data centres and other high-speed networks. Some key features of OM5 are: Supports SWDM (Short Wavelength Division Multiplexing): OM5 enables multiplexing of multiple wavelengths, increasing data transmission capacity. High speed over short distances: OM5 is suitable for speeds of 40 Gbit/s, 100 Gbit/s and even 400 Gbit/s and was developed for transmissions up to around 150 metres. Backwards compatible: OM5 can also be used with OM3 and OM4 cables and is therefore ideal for upgrades in existing networks. Fibre optic types such as OM5 are defined in standards such as ISO/IEC 11801 and DIN EN 50173. Both standards ensure that cabling systems offer high performance and future-proofing by defining and certifying OM5 for applications with SWDM and for high-speed connections over short distances.

Most common plug shapes

Fibre optic technology has many different connectors. The following overview shows the most common types.

Lucent-Anschluss

The "Lucent Connector" (LC) is known as the standard for LAN cabling in data centres. It is equally suitable for single and multimode. Thanks to its compact size, it requires little space in the control cabinet. And the automatic locking and unlocking when plugging in or unplugging (push-pull locking) makes installation easier.

Subscriber Connector

The "Subscriber Connector" (SC) is the direct predecessor of the LC. This connector is also single- and multimode-capable and equipped with push-pull locking.

Straight Tip

The "Straight Tip" (ST), also known as the "BOFC connector", is still widely used as the former standard for LAN cabling. It is equipped with a bayonet lock and is suitable for single and multimode.

MTRJ

The design of the "MTRJ" is reminiscent of an RJ45 plug and enables a high assembly density and quick, simple installation. The "MTRJ" is single and multimode capable.

E2000

The single- and multimode-capable "E2000" compact connector is the standard for WAN and MAN cabling. Its push-pull locking mechanism with integrated cap protects the connector from dust and the eyes from harmful laser beams.

Cable colours

Fibre optic cables can be identified by their cable colours:

OM1

OM1 cables are orange.

OM2

OM2 cables are orange.

OM3

OM3 cables are aqua-coloured.

OM4

OM4 cables are purple or magenta-coloured.

OM5

OM5 cables are neon green.

InLine Products

The InLine fibre optic assortment comprises over 280 articles. From audio cables and patch cables to adapters and
converters

InLine® Fiber optical Adapter duplex LC/LC female MultiMode ceramic sleeve

These InLine® fibre optic adapters are bush mounts that allow for extremely precise coupling and alignment of optical connectors thanks to the internal ceramic or metal ferrule. These optical couplers are equipped with flanges and/or screws for mounting on optical patch panels, optical distribution trays and panels, optical wall boxes and more.

LC/LC Duplex Coupler for multimode/multimode optical fibres.
Ceramic ferrule/socket.
Plastic body in beig colour.
Panel anchoring by Keystone type system.

Item no.: 89989L

InLine® Fiber Optical Adapter Duplex LC/LC MM Ceramic Sleevewith Flange grey

Fiber Optic Adapter with flange for installation

Duplex LC connector on both sides
Multimode
Coupling for installation
Plastic version, beige
Ceramic sleeve
Breakthrough opening about 13x10mm, hole spacing approx. 18mm

Item no.: 89989K

InLine® Fiber Optical Adapter Duplex LC/LC SM Ceramic Sleeve blue

LC/LC Duplex coupler for singlemode/singlemode optical fibres.
Ceramic ferrule/socket.
Blue plastic body.
Panel anchoring by means of clips.
Compatible with PC, UPC and APC

Item no.: 89989D

InLine® Fiber Optical Adapter Duplex SC/SC MM Ceramic Sleeve with Flange grey

Fiber coupling to connect/adaptation of fiber optic cable

Connector duplex SC female to duplex SC female
for multimode fiber
ceramic sleeve inside
Breakthrough opening about 26x10mm, hole spacing approx. 31mm

Item no.: 89992A

InLine® Fiber Optical Adapter Duplex SC/SC single mode ceramic sleeve blue

SC/SC Duplex coupler for singlemode/singlemode optical fibres.
Metal ferrule/socket.
Blue plastic body.
Panel anchoring by means of clips and screws (not included).
Compatible with PC, UPC and APC

Item no.: 89992S

InLine® Fiber Optical Adapter Duplex ST/SC male grey metal sleeve with flange

ST/SC Duplex sleeve for multimode/multimode optical fibres.
Ceramic ferrule/socket.
Plastic body in beig colour.
Panel anchoring by means of clips and screws (not included).

Item no.: 89991D

InLine® Fiber Optical Adapter Metal Duplex LC/LC MM Ceramic Sleeve with Flange

Fiber Optic Adapter with flange for installation

Duplex LC connector on both sides
Multimode
Coupling for installation
Metal version
Ceramic sleeve
Breakthrough opening about 13x10mm, hole spacing approx. 18mm

Item no.: 89989M

InLine® Fiber Optical Adapter Metal Duplex LC/LC SM Ceramic Sleeve with Flange

Fiber Optic Adapter with flange for installation

Duplex LC connector on both Sides
Single Mode
Coupling for installation
Metal version
Ceramic sleeve
Breakthrough opening about 13x10mm, hole spacing approx. 18mm

Item no.: 89989E

InLine® Fiber Optical Adapter Metal Duplex ST/ST MM Ceramic Sleeve with Flange

Fiber Optic Adapter with flange for installation

Duplex ST connector on both sides
Multi Mode
Coupling for installation
Metal version
Ceramic sleeve
Breakthrough opening about 20x9mm, hole spacing approx. 31mm

Item no.: 89990C

InLine® Fiber Optical connector Simplex ST/ST multimode metal sleeve

Fiber coupling to connect/adaptation of fiber optic cable

Connector simplex ST female to simplex SC female
for multimode fiber
metal sleeve inside

Item no.: 89990B

Connections

Fibre optic cables (optical fibre cables) can be connected in various ways. Here are the most common methods:

Plug connections:

With this method, pre-assembled connectors are used to connect the cables together.

Fusion splicing

Two glass fibres are fused together to create a continuous fibre strand. Fusion splicing requires special splicing equipment and provides a very low-loss and stable connection

Micro splicing

(Mechanical splicing) This method uses mechanical connections in which the fibres are fixed using a gel or clamp. Mechanical splicing is faster but has a slightly higher attenuation value than fusion splicing.

Coupler (splitter and distributor):

In some networks, special couplers are used to split a single optical fibre into several signal paths.

Application in other areas

When transmitting audio signals, fibre optic cables contribute to high sound quality thanks to their low susceptibility to interference and their level fidelity. The common cable standard is the Toslink cable for audio devices with an SPDIF interface.

The interference-resistant fibre optic cables are also being used more and more in vehicles. The biggest advantage is that they replace entire cable harnesses with a single cable, thus helping to reduce vehicle weight and fuel consumption.

InLine® Optical Audio Cable Toslink male / male 1m

7 Variants available.

InLine® Optical audio cable, toslink M/M

Cable to connect device like Hi-Fi amplifiers, TV, SAT-receiver, DVD-player etc. by the optical audio connector.

2x Toslink male plug