Abstract: A wavelength converter for binary optical signals includes an interferometer structure (110) for generating an output signal by modulating a received local signal (LS) according to the modulation of a fUrther received first input signal (IS 1). When such interferometer structures (110) are operated in a standard mode it is known in the art to control the power of the input signal such that the extinction ratio of the output signal is kept minimal. The invention also controls the power of the input signals to achieve the minimal extinction ratio when the wavelength converter and in particular the interferometer structure (110) is operated in a differential mode receiving two input signals.

Abstract: The invention relates to a wavelength converter for binary optical signals comprising an interferometer structure (110) for generating an output signal by modulating a received local signal (LS) according to the modulation of a further received first input signal (IS1). When such interferometer structures (110) are operated in a standard mode it is known in the art to provide a control means for controlling the power of the input signal such that the extinction ratio of the output signal is kept minimal. The invention provides a modified control means for also achieving the minimal extinction ratio when the wavelength converter and in particular the interferometer structure (110) is operated in a differential mode receiving two input signals.