Optimisation of a reconfigurable free-space fibre switch in the WDM 1,55 µm window

In the framework of optical transport networks based on wavelength division multiplexing, (WDM), one of the most critical elements is the optical cross-connect [1] (OXC). At the core of many cross-connect architectures is a space-switching stage, operating in the 1.55 telecom wavelength window. An important feature is that the device routing peformance must be polarisation insensitive, with moderate insertion loss and reconfiguration rates lower than the microsecond.