INTERFEROMETER OPTICAL SWITCH AND VARIABLE OPTICAL ATTENUATOR

摘要

The present invention discloses an interferometer optical switch that can carry out switching over a broad band and has a high extinction ratio and large fabrication tolerance.The optical multi/demultiplexing device employs a phase generating coupler(111), the phase difference of the output of which has wavelength dependence, as at least one of the optical multi/demultiplexing device included in the interferometer optical switch. A wavelength insensitive interferometer optical switch is implemented by making the sum 2À{Æ 1 (») + Æ” L (») + Æ 2 (»)} constant regardless of the wavelength, where Æ 1 (») is the phase produced by the phase generating coupler (111), Æ” L (») is the phase difference of the optical delay line (131) with an optical path length difference of ”L, and Æ 2 (») is a phase difference between light rays output from a directional coupler (153).