Patent ID: 8466831

Claim:
Optical modulator, comprising an input suitable to receive an optical carrier, a high-frequency input and an output suitable to transmit an optical signal, the optical modulator comprising two Mach-Zender ( 1 , 2 ) modulators in parallel between the input and output, which constitute two different optical paths, the whole circuit constituting a third Mach-Zender modulator ( 3 ), the optical modulator being characterised in that: the first Mach-Zender modulator ( 1 ) is provided with an electrode suitable to carry, inside the modulator ( 1 ), two signals (RF 1 , RF 2 ), each obtained by the sum of the two tones f R and f D , of equal power but dephased of π/2, being further provided an electrode (Bias 1 ) for realising a Single Side Band modulation of the tones f R and f D ; the second Mach-Zender modulator ( 2 ) is biased by means of a DC electrode (Bias 2 ); the third Mach-Zender modulator ( 3 ) comprising an electrode (Bias 3 ) suitable to introduce a proper additional dephasing aimed at realising the reversal of the optical carrier phase of the signals deriving from the first ( 1 ) and the second ( 2 ) Mach-Zender modulator before the output, so as to suppress the optical carrier by means of destructive interference and thus obtaining only the tones f R and f D in the optical spectrum.