Fusion splicing is the most widely used method of splicing as it provides for the lowest loss and least reflectance, as well as providing the strongest and most reliable joint between two fibers. Virtually all singlemode splices are fusion. Fiber optic splicing is the process of joining two fiber optic cables together so that light signals can pass with minimal loss or reflection. The goal is to achieve the lowest possible optical loss (signal. This guide reveals the secrets to fusion splicing with little fluff—just proven, straightforward techniques refined from years of work in the field. There are numerous use cases for fiber optic splicing. As. It is a technique that uses controlled heat to permanently fuse two optical fiber ends together.