Types of Fiber Splices Used

Mechanical splices hold two cleaved fiber ends together. A viscous substance called "index matching gel", pre-installed in the splice body, helps to reduce fresnel reflections and optical attenuation.

Mechanical splices are low cost, quick to install, and can provide a quality fiber connection. Because they are highly reflective, mechanical splices are usually used on multimode fiber.

Fusion splices are the highest quality splices available to the fiber optic installer. Fusion splicers are complex machines that weld two fiber ends together. When properly performed, a fusion splice will have less than .1dB of loss, and will have no reflection, as the light rays do not pass through a boundary to create the fresnel effect-the two fiber ends have been melted into one.

Fusion splicers require careful setup and complete cleanliness for proper performance. Environmental conditions such as humidity, room temperature, and barometric pressure can cause poor splices. The splicer will have field adjustments that can adjust for adverse conditions. It may take a few experimental splices with various settings to compensate for difficult conditions.