Fibre to Fibre Connections

Introduction:

Two fibre may be joined either b splicing, which is a permanent join, or by a connection which is permits repeat coupling and uncoupling. Permanent splices have applications in long distance communication links and in the construction of integrated fibre sensor systems. Connectors are used to couple fibre transmitter and receiver modules, and devices in optical communication system.

Both types of join have the following requirements:

1) The fibre end faces must optically flat and perpendicular to the fibre axis.

2) The two fibres to be joined must be perfectly aligned.

3) The joint needs to be mechanically strong and the procedure itself must be simple and easily carried out in the field.

Experiments:

Part I, Mechanical Splice – “Ultra Splice”

This technique archive insertion losses of ~0.01dB and the mechanical strength of the join is ~60% of the original fibre strength. Other splicing methods depend on precision aligned groove techniques. The fibres to be joined are inserted into the groove and held in place either by an index-matching epoxy or by purely mechanical mean. The advantage of these methods is that they are quick and simple procedures and untrained operators can routinely achieve losses of ~0.1-0.3dB.

In the experiment, we have power in 3.00mW and power out 2.85mW, then the lost in dB is:

Loss in dB = -10 x log(2.8/3.0) = 0.22dB

Part II, Fusion Splice

Thermal fusion is the highest quality splice. In this process the fibres are aligned with precision stages under microprocessor control. A plasma touch or an electric are is the passed across the junction of the fibres fusing them together. It has typical losses about 0.1dB.

Fitel Fusion Splicer

In the experiment, we had power in 3.00mW and power out 2.90mW, the loss in dB :

Loss in dB = -10 x log(2.90/3.00) = 0.15dB

Conclusion:

In this experiment we were introduced two types of splicing, the mechanical splicing and thermal fusion splicing. The data we got during the experiment is close to or in the range of the typical value. Fusion splicing produces lower loss and less back reflection than mechanical splicing, because the resulting fusion splice points are almost seamless.

Picture Reference:

http://www.tecratools.com/pages/tecalert/splicing_guide.html
http://www.alsys.ro/en/networking/networking.php