Fusion Splicer Basics

What does a Fusion Splicer do?

A Fusion Splicer is used for combining or splicing two optical fibers end to end via fusion. The objective here is to fuse the fibers together in such a way that no light is reflected or refracted and having the spliced fiber be as strong as the regular fibers.


Types of Fusion Splicers

  • Single Fiber Fusion Splicer: These can only splice 2 fibers at a time. One fiber is stripped and cleaned and inserted into the machine. The same process is applied to the second fiber. The splicer can take up to 10 seconds to splice the fibers and will also give an estimation on the loss of light. Single fiber splicers can splice fibers between 250 and 900-micron, flat drop cables, and splice on connectors.
  • Mass Fusion Splicer: Mass fusion splicers can splice 1 to 12 fibers at a time. They are not as popular as single fiber splicers but if you need to splice more than one fiber at a time, they can be very efficient.
  • Core-Core Alignment Fusion Splicer: This is the most commonly used fusion splicer technology. It uses light and image detection in order to look at the fiber cores to measure and monitor the core position while aligning the fiber cores. This gives a precise fiber alignment, giving a typical loss of only 0.02db. Although this technology is expensive, but it is also powerful, flexible, and efficient.
  • Cladding Alignment Fusion Splicer: Basic fusion splicers use cladding alignments to line up the fibers. They sit in a V-groove and are lined up based on outer diameter. This is a fast method for splicing and it is low cost which is why it is usually used on low cost fusion splicers. Even though the outer diameters are aligned doesn’t mean that the fibers are perfectly aligned which results in higher loss splices. Being a low-cost solution also means that it lacks the features a higher end splicer might have.


Fusion splicing is useful in any instance where optical fibers are used. Uses such as telecommunication and networking, power transmissions, and sensors. All these applications are improved with fiber optics so having a fusion splicer will come in handy.


Factors Affecting Selecting a Fusion Splicer

Mechanisms of Attenuation

Attenuation, also known as loss of light or transmission loss, is the reduction in the intensity of the light signal as it travels through the fiber cables. Attenuation uses dB/m as its units. Attenuation is an important factor in choosing your fusion splicer.

Light Scattering

  • Propagation of light through a cable is dependent on total internal reflection of the light wave.
  • Irregular surfaces can cause the light signal to be reflected in random direction.
  • Depends on the wavelength of the light being scattered.
  • Visible light has a wavelength of one micrometer, which can cause the scattering to have dimensions of similar scale.

UV-Vis-IR Absorption

  • Attenuation can occur because of the selective absorption of certain wavelengths.
  • At the electronic level, it depends on whether electron orbitals are quantized such that they can absorb light of a specific wavelength. This can cause a change in color.
  • At an atomic level it depends on chemical bonds, atom spacing, and whether the molecules have a long-range order.
  • UV and infrared (IR) absorption occurs when the selected wavelength frequencies align with the frequency at which the particles in the material vibrate.

Loss Budget

  • Attenuation is increased by the inclusion of connectors and splices.
  • When computing acceptable attenuation keep 3 things in mind:
    • dB loss due to length and type of cable.
    • dB loss due to connectors.
    • dB loss due to splicing.
  • Connectors introduce around 0.03dB per connector.
  • Total loss can be calculated with the formula:
    • Loss = (dB loss per connector × number of connectors) + (dB loss per splice × number of splices) + (dB loss per kilometer × kilometers of fiber)
  • The calculated loss is used when testing to confirm the measured loss.



  • Most commonly used material.
  • Good for transmission of a wide range of wavelengths.
  • Can be used at reasonably high temperatures.
  • Has high mechanical strength; good for bending.
  • Can be doped with various other materials.
  • Has high threshold for damage.

Fluoride Glass

  • Heavy fluoride glass has very low attenuation.
  • Difficult to manufacture.
  • Poor resistance to environmental factors such as moisture.
  • Good for mid infrared range (2000-2500 nm).

Phosphate Glass

  • Can be more advantageous over silica with a high concentration of doping ions.
  • Crystallizes in at least 4 different forms.

Chalcogenide Glass

  • Elements in group 16 of the periodic table.
  • React more with electropositive elements.
  • Versatile compounds.
  • Can be crystalline, amorphous, metallic, or semi conducting.
  • Can be used for far infrared transmissions.


The most important factor at play would be cost. You will need to balance which features you want and are most important to you with which features you are willing to sacrifice. Finding a fusion splicer that fits your needs may be difficult, but GAO Tek Inc offers many different fusion splicers for any budget.



Fusion Splicing Process


Prepare Fibers for Splicing

  • Clean fibers.
  • Strip off buffer coating.
  • Clean bare fiber with proper materials.
  • Place fibers into the guides in the fusion splicer and clamp into place.


Run Splicer Program

  • Choose the program on the splicer.
  • The splicer should show the fibers placed inside of it.
  • Fibers will be inspected, and bad fibers will be rejected.
  • Splicers will be moved into position.
  • Dirt will be removed
  • Fibers will be preheated.
  • Fibers will be aligned.
  • Fibers will be fused by an automatic cycle that feeds the fibers together at a controlled rate.
  • When completed the splicer will give a loss estimate.
  • A permanent splice protector will be attached.



Checking the Finished Splice

  • Inspect the splice.
  • Make sure there are no flaws such as bubbles, bulges, shadows, or lines.
  • Redo splices if necessary.



At GAO Tek Inc, the Fusion Splicer offered range from basic, affordable models to high end, advanced models. The Fusion Splicers for sale should satisfy any needs the customer has and more.

If you have any specific needs, GAO Tek Inc also offers custom Fusion Splicers with any specification you desire. Feel free to contact GAO Tek Inc if you are looking to purchase a Fusion Splicer that does not appear for sale on the website or if you would like to customize a Fusion Splicer that is for sale please feel free to contact us.


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