Patent attributes
An integrated optical add/drop device having switching function for use in wavelength division multiplexing optical communication systems, has first and second optical couplers between which first and second interferometric arms of an interferometer are extended. The integrated optical add/drop device has an optical filter having first and second input ports connected to first portions of the first and second interferometric arms and first and second output ports connected to second portions of the first and second interferometric arms. The optical filter acts as a selective switch exchanger for exchanging between one interferometric arm and the other at least one of a plurality of optical signals S (λ1), S (λ2), . . . , S (λn), received at its input ports and for transmitting the remaining optical signals through its output ports in the first and second interferometric arms. The integrated optical add/drop device also has at least first and second optical shifters located on opposite sides of the optical filter.