Four-port multimode interconnectable star coupler

The author reports design consideration of a novel multimode interconnectable star coupler in which each port acts as both an input and output port. He reports fabrication and characterisation of the four-port interconnectable star coupler in the form of an optical integrated circuit on a polymer substrate. The interconnectable star coupler exhibits an excess loss of 2.65 dB and a return light loss of 34.2 dB.