Patent ID: 6934473

Claim:
An optical system comprising: at least a first optical transmitter configured to transmit information via optical signals including at least one signal wavelength; an add/drop device configured to receive the optical signal from said first optical transmitter, said add/drop device including: a 1×N device having an input port for receiving optical signals from the transmitter, and having N output ports, wherein one of the output ports is part of an input path; a first selective element configurable to pass a first signal wavelength from said input path to a first add/drop path and pass continuing signal wavelengths differing from the first signal wavelength to a second add/drop path; a second selective element configurable to pass a second signal wavelength from said first add/drop path and continuing signal wavelengths differing from the second signal wavelength from said second add/drop path to an output path and pass the second signal wavelength from said second add/drop path and signal wavelengths differing from the second signal wavelength from said first add/drop path to a drop path; an N×1 device having an output port for providing output signals from the add/drop device, and having N input ports, wherein one of the input ports is part of the output path, and wherein at least one other of the input ports is connected to at least one corresponding output port of the 1×N device; at least a first optical receiver configured to receive the output signal from said add/drop device; and at least a second optical receiver configured to receive the drop signal from said add/drop device.