Switch/variable optical attenuator (SVOA)

A method of manufacturing a Switch/Variable Optical Attenuator (SVOA), the method comprising:

• fabricating at least one 2×2 optical switch on a die;
• fabricating a respective integral variable optical attenuator for each of said at least one 2×2 optical switches on the die;
• wherein each of said at least one 2×2 optical switches comprises an input optical port, an output optical port, an add optical port, and a drop optical port, said input optical port being connected to said output optical port in one state of said at least one 2×2 optical switch and said add optical port being connected to said output optical port in a second state of said at least one 2×2 optical switch;
• and
• fabricating an optical connection between said output optical port of each of said at least one 2×2 optical switches and an input of its respective integral variable optical attenuator.

A Reconfigurable Optical Add Drop Multiplexer (ROADM) comprising:

• an optical demultiplexer to receive a first multiplexed optical signal and to output a plurality of demultiplexed optical signals;
• a plurality of Switch/Variable Optical Attenuators (SVOAs) to respectively receive said plurality of demultiplexed optical signals and to selectively output a plurality of switched/attenuated optical signals;
• and
• an optical multiplexer to receive said plurality of switched/attenuated optical signals from said plurality of SVOAs and to output a second multiplexed optical signal;
• wherein each of said SVOAs comprises:
• a die including at least one 2×2 optical switch and a respective integral variable optical attenuator for each of said at least one 2×2 optical switches;
• wherein each of said at least one 2×2 optical switches comprises an input optical port, an output optical port, an add optical port, and a drop optical port, said input optical port being connected to said output optical port in one state of said at least one 2×2 optical switch and said add optical port being connected to said output optical port in a second state of said at least one 2×2 optical switch;
• and
• wherein said output optical port of each of said at least one 2×2 optical switches is optically connected to an input of its respective integral variable optical attenuator.

A method of manufacturing a Reconfigurable Optical Add Drop Multiplexer (ROADM), the method comprising:

• fabricating an optical demultiplexer to receive a first multiplexed optical signal and to output a plurality of demultiplexed optical signals;
• fabricating a plurality of Switch/Variable Optical Attenuators (SVOAs) to respectively receive said plurality of demultiplexed optical signals and to selectively output a plurality of switched/attenuated optical signals;
• and
• fabricating an optical multiplexer to receive said plurality of switched/attenuated optical signals from said plurality of SVOAs and to output a second multiplexed optical signal;
• wherein each of said SVOAs is manufactured by a method that comprises:
• fabricating at least one 2×2 optical switch and a respective integral variable optical attenuator for each of said at least one 2×2 optical switches on a die;
• wherein each of said at least one 2×2 optical switches comprises an input optical port, an output optical port, an add optical port, and a drop optical port, said input optical port being connected to said output optical port in one state of said at least one 2×2 optical switch and said add optical port being connected to said output optical port in a second state of said at least one 2×2 optical switch;
• and
• fabricating an optical connection between said output optical port of each of said at least one 2×2 optical switches and an input of its respective integral variable optical attenuator.

A method of operating a Reconfigurable Optical Add Drop Multiplexer (ROADM), the method comprising:

• inputting a first multiplexed optical signal to an optical demultiplexer, the optical demultiplexer outputting a plurality of demultiplexed optical signals;
• respectively inputting the plurality of demultiplexed optical signals to a plurality of Switch/Variable Optical Attenuators (SVOAs), the plurality of SVOAs respectively selectively outputting a plurality of switch/attenuated optical signals;
• and
• inputting the plurality of switch/attenuated optical signals to an optical multiplexer, the optical multiplexer outputting a second multiplex optical signal;
• wherein each of the plurality of SVOAs includes at least one 2×2 optical switch and respective integral variable optical attenuator on a die, the at least one 2×2 optical switch receiving one of the plurality of demultiplexed optical signals and the respective integral variable optical attenuator outputting one of the plurality of switch/attenuated optical signals.