Insertion Loss
The insertion loss of a fiber optic splitter refers to the number of dB of optical power loss for each output relative to the input. Generally, a smaller insertion loss value is better.
Splitting Ratio
The splitting ratio is defined as the ratio of the output power of each output port of the fiber optic splitter. Typically, PLC fiber optic splitters have an evenly distributed splitting ratio, while fused biconical taper (FBT) splitters can have unequal splitting ratios. The specific splitting ratio depends on the wavelength of the transmitted light. A fiber optic splitter might have a 50:50 splitting ratio for 1.31 μm light, but this changes to 70:30 when transmitting 1.5 μm light (this occurs because fiber optic splitters have a certain bandwidth, i.e., the frequency band width of the transmitted optical signal where the splitting ratio remains essentially constant).
Isolation
Isolation refers to the ability of a fiber optic splitter to isolate the optical signal in one optical path from the optical signals in other optical paths.
Return Loss
Return loss, also known as reflection loss, refers to the power loss of the optical signal that is returned or reflected due to discontinuities in the fiber or transmission line. A higher return loss is better, as it reduces the impact of reflected light on the light source and the system.
