What is Fiber Optic Cable Splicing and How to do it?

What is Optical Fiber Optics?

Fiber optics is a technology that uses glass or plastic fiber strands to send and receive data in the form of light over long distances.

What is fiber optic cable splicing?

Joining two fiber optic cables together is known as fiber optic splicing.

Termination or connectorization is the most common method of joining or splicing the fibers.

When compared to termination, fiber splicing typically results in less light loss and back reflection.

We can do fiber optic splicing by two methods. They are

•Fusion Splicing

•Mechanical Splicing

Fusion Splicing

Fiber optic splicing is a splicing technique in which a machine is used to precisely align the two ends of the fiber and then “fused” or “welded” the ends of the glass together using a specific type of thermal or electric arc. Fusion splicing ensures a continuous connection between optical fibers, resulting in very low optical transmission losses. Typical loss: 0.1dB

Mechanical Splicing

A mechanical splice is a connection between two or more optical fibers that are held in place by a self-contained assembly that aligns and secures them.

Actually, fibers are not joined permanently, it is simply held together in a particular alignment that makes the passage for light from one fiber to the other.

The typical loss is 0.3 decibels.

How to do Splicing?

Fusion Splicing method

As mentioned earlier, fusion splicing is the joining of two or more optical fibers that are tightly bonded by welding them together using an electromagnetic arc.

There are four steps to make the splicing proper. They are

Step 1: Fiber should be prepared

Remove all sheaths, jackets, tubes, strength members, and other materials to reveal only the bare fiber. The most important factor in this step is cleanliness.

Step 2: Split the fiber

The use of a good fiber optic cutter is essential for a successful fusion splice. The cut end must be mirror-smooth and perpendicular to the fiber axis to ensure a proper connection. Note: The cutter does not cut the fibers! It simply cuts the fibers and then pulls or bends them to create a clean break. The goal is to make the vertical cut end as perfect as possible. This is why a good flash welding knife can often cost between $1,000 and $3,000. This cutter can reliably produce a cutting angle of 0.5 degrees or less.

Step 3: Fiber Melting

This step consists of two steps: Leveling (alignment) and Heating. Leveling can be manual or automatic, depending on the type of equipment. The more expensive the equipment, the more accurate the alignment. When properly aligned, a fusion splicer uses an electric arc to melt the fiber and continuously weld the two ends of the fiber together.

Step 4: Fiber protection

The fibers are protected from bending and tensile forces, ensuring that the joint does not break under normal use. A typical fusion splice has a tensile strength of 0.5 to 1.5 pounds and will not break under normal handling conditions; however, it must be protected from excessive bending and pulling forces. Heat shrinks tubing, silicone gel, and/or mechanical crimp protectors can be used to protect joints from external elements and breakage.

Mechanical splicing Method

Mechanical splicing is an optical junction in which the fibers are aligned precisely and held in place by a self-contained assembly rather than a permanent bond. The two fiber ends are aligned to a common centreline, and their cores are aligned so that light can pass from one fiber to the next using this method.

A mechanical splice is performed in four steps just like the fusion splicing

Step 1:

The first step is to prepare the fiber. Protective coatings, jackets, tubes, strength members, and other materials should all be removed, leaving only the bare fiber visible. The most important consideration is cleanliness.

Step 2: Cleave the fiber

This process is similar to fusion splicing chipping, but the accuracy of the chipping is not very important.

Step 3: Mechanical fiber bonding

This method does not use heat. Simply place the fiber ends together inside a mechanical splice. An index-matched gel inside the mechanical splicer helps to pass the light from one end of the optical fiber to the other. Use epoxy resin in the older devices than index-matched gel. It helps to hold the cores together.

Step 4: Secure the optical fiber

The finished mechanical joint provides self-protection.

Difference between Mechanical and Fusion Splicing

Parameters Mechanical Splicing Fusion Splicing
Initial Cost Low High
Performance Can be used with both single mode and multi-mode fiber Used with single-mode fiber
Speed Faster Slower compared to mechanical splicing
Insertion loss 0.5dB Less than 0.1dB
Splicing loss 0.3dB 0.1dB