5 dB depending on splitter type. Optional: patch panels, attenuators, or extra components. Helps cover dirt, aging, and measurement tolerances. Calculate insertion loss for passive optical splitters in PON and distribution networks. DISCLAIMER: These calculators are provided for. Optical splitters, encompassing FBT (Fused Biconical Taper) couplers and PLC (Planar Lightwave Circuit) splitters, are prevalent passive optical devices designed to divide fiber optic light into multiple segments based on a specified ratio. Common values: 2, 4, 8, 16, 32, 64. Optical splitters, including FBT couplers and PLC. In fiber optic networks, particularly in FTTx (Fiber to the x) and PON (Passive Optical Networks) deployments, splitters play a central role in distributing the optical signal from a single source to multiple destinations.