Apparatus for shaping binary optical signals, and use thereof to modify said signals

A method of modifying an input binary optical signal in the form of a first light wave modulated between low and high power levels, said method comprising the steps of:

• applying said input signal to a shaping apparatus comprising:
• a first stage for delivering a modulating optical signal as a function of said input signal, the modulating signal being in the form of a second light wave of determined wavelength and being modulated between first and second power levels, the high level of said first and second levels being stabilized so as to be substantially independent of fluctuations of said low and high levels of the input signal;
• and a second stage comprising an interferometer structure coupled to said first stage to receive said modulating signal and deliver an output signal that is the result of constructive interference between first and second auxiliary waves when the power of the modulating signal is equal to said first power level and the result of destructive interference between said first and second auxiliary waves when the power of the modulating signal is equal to said second level;
• and
• power modulating said auxiliary waves.

A method of modifying an input binary optical signal in the form of a first light wave modulated between low and high power levels, said method comprising the steps of:

• applying said input signal to a shaping apparatus comprising:
• a first stage for delivering a modulating optical signal as a function of said input signal, the modulating signal being in the form of a second light wave of determined wavelength and being modulated between first and second power levels, the high level of said first and second levels being stabilized so as to be substantially independent of fluctuations of said low and high levels of the input signal;
• and a second stage comprising an interferometer structure coupled to said first stage to receive said modulating signal and deliver an output signal that is the result of constructive interference between first and second auxiliary waves when the power of the modulating signal is equal to said first power level and the result of destructive interference between said first and second auxiliary waves when the power of the modulating signal is equal to said second level, said interferometer structure comprising first and second light guide branches respectively receiving first and second portions of a third light wave via first coupling means, said branches being respectively provided with first and second semiconductor optical amplifiers, said first amplifier receiving said modulating signal via second coupling means, said first and second amplifiers being fed with electric currents adjusted to deliver said first and second auxiliary waves, respectively;
• and
• power modulating said third light wave.

A method of modifying an input binary optical signal in the form of a first light wave modulated between low and high power levels, said method comprising the steps of:

• applying said input signal to a shaping apparatus comprising:
• a first stage for delivering a modulating optical signal as a function of said input signal, the modulating signal being in the form of a second light wave of determined wavelength and being modulated between first and second power levels, the high level of said first and second levels being stabilized so as to be substantially independent of fluctuations of said low and high levels of the input signal, said first stage including a semiconductor amplifier suitable for receiving said input signal and a further light wave, wherein said amplifier and/or said input signal are dimensioned to place said amplifier in a gain-saturation state when the input signal is in the high state, and wherein said modulating signal is constituted by said further light wave amplified by said amplifier;
• and a second stage comprising an interferometer structure coupled to said first stage to receive said modulating signal and deliver an output signal that is the result of constructive interference between first and second auxiliary waves when the power of the modulating signal is equal to said first power level and the result of destructive interference between said first and second auxiliary waves when the power of the modulating signal is equal to said second level;
• and
• power modulating said further light wave.

A method of modifying an input binary optical signal in the form of a first light wave modulated between low and high power levels, said method comprising the steps of:

• applying said input signal to a shaping apparatus comprising:
• a first stage for delivering a modulating optical signal as a function of said input signal, the modulating signal being in the form of a second light wave of determined wavelength and being modulated between first and second power levels, the high level of said first and second levels being stabilized so as to be substantially independent of fluctuations of said low and high levels of the input signal, said first stage including a semiconductor amplifier suitable for receiving said input signal and a further light wave, wherein said amplifier and/or said input signal are dimensioned to place said amplifier in a gain-saturation state when the input signal is in the high state, and wherein said modulating signal is constituted by said further light wave amplified by said amplifier;
• and a second stage comprising an interferometer structure coupled to said first stage to receive said modulating signal and deliver an output signal that is the result of constructive interference between first and second auxiliary waves when the power of the modulating signal is equal to said first power level and the result of destructive interference between said first and second auxiliary waves when the power of the modulating signal is equal to said second level;
• and
• modulating the electric current applied to said amplifier.