Mode multiplexer / demultiplexer and mode multiplex transmission system

摘要

PROBLEM TO BE SOLVED: To provide a mode multiplexer/demultiplexer capable of multiplexing/demultiplexing a desired mode, at a low loss, in a wide wavelength which is used in a wavelength multiplexing optical communication system in a wide wavelength band of C-band to L-band.SOLUTION: The mode multiplexer/demultiplexer includes: a waveguide 11 and a waveguide 12; a coupling part 21 that couples a beam of propagation light from the waveguide 11 with a first mode in the waveguide 12; a coupling part 22 that couples a propagation light from the waveguide 11 with a second mode different from the first mode in the waveguide 12; and a delay part 23 which is disposed between the coupling part 21 and the coupling part 22 to generate a delay in the optical path length on the waveguide 11 and waveguide 12.SELECTED DRAWING: Figure 2