A wavelength division multiplexed (WDM) reconfigurable optical switch, the switch has at least one optical input port to receive a WDM input optical signal comprising a plurality of wavelength channels; a plurality of optical output ports; a reconfigurable holographic array on an optical path between the at least one optical input port and the plurality of optical output ports; and at least one diffractive element on an optical path between at least one optical input port and the reconfigurable holographic array, to demultiplex the WDM input optical signal into a plurality of demultiplexed optical input beam channels, and to disperse the demultiplexed optical input beam channels spatially along a first axis on said the reconfigurable holographic array; and the switch further comprises one or more beam profiling optical elements to modify transverse beam profiles of the demultiplexed optical input beam channels.