Fiber optic connecting procedure - Fusion Splicing

The fusion splicing is the method of connecting two fiber optic cable by melting the ends together using an electric arc. A splicing machine used to do this, the machine first has to align the cores and then apply the exact amount of heat to melt the ends before pressing them together.

Basically, there are four steps for splice method:

  • Stripping
  • Cleaving
  • Fusion process
  • Put the protector

Fusion Method:


Strip the external coating on the wire, Cut back the aramid strength member using ceramic or kevlar scissors. Strip the primary buffer from the fiber using fiber strippers, not ordinary wire strippers. Do this carefully to prevent the fiber breaking, only a fine cut should be made.



The cleaver first scores the fiber and then pulls the fiber apart to make a clean break. It is important to make a clean break and smooth ends. Cleavers vary from manufacturer to manufacturer and you should read the instructions for the one you are using. Basically, the operation consists of putting the fiber into the groove and clamping, then close the lid and press the lever.

The Fusion Process:

After the fibers are prepared they are placed in the fusion splicer. Further process will be carried out by the splicer automatically. First, the two fibers are aligned, you can see this on the photo.

The splicer aligns the fibers on one axis and then from another camera angle set at 90 degrees, aligns with the other axis. This high precision alignment is critical to a low loss joint, any mismatch of the fiber cores will significantly reduce the spread of light through the joint.

Once the fibers are perfectly aligned, the splicer fires an electric arc between the two ends that melts them immediately and pushes them together or fuses them into a single fiber.



The splicer may contain built in the heat shrink oven. When the fiber is removed from the machine, the protective tube slides into place and the whole assembly is placed in the oven to shrink the tube to the splice. This protective tube gives the fiber physical protection.