Couplers, Splitters and PLC’s are passive optical devices that are used to split an optical signal into at least 2 and as many as 64 signals. They are widely used in FTTx architectures to provide service for up to 64 users from a single optical signal. Wave Division Multiplexers (WDM’s) allow signals of different wavelengths to be sent down a single optical fiber at the same time without interfering with each other. This increases the bandwidth the fiber is able to carry at one time.
