Electro-optic multimode multiplexer

This paper describes the construction and performance of an optical time-division multiplex device that is capable of interleaving two optical bit-streams onto one fiber-optic transmission line, and of separating those signals at the receiving end. The device has four ports that interface with multimode fibers, a single strand of fiber being used for each information channel. To our knowledge, this is the first report of a multimode mux/demux device for fiber optics. The operating principles are similar to those of a prior switch (1), but the present device incorporates several improvements: a shorter interaction length (0.4 cm vs 1.3 cm), a more circular channel cross-section for better fiber-matching, and a higher on/off switching ratio (9.0 dB vs 7.1 dB).