Optical wavelength converter control method and device

Method of controlling an optical wavelength converter according to a required output wavelength, said wavelength converter having an optical signal input to which is applied an input optical signal whose wavelength is to be converted, an optical signal output at which appears an output optical signal whose wavelength is the required wavelength, and at least one control electrode to which is applied a respective analog electrical control signal to control the wavelength of the output optical signal, said method comprising:

• a calibration phase comprising the steps:
• establishing a mathematical relationship between the magnitude of said electrical control signal and the wavelength of said output optical signal, and
• storing said mathematical relationship in an addressable digital storage means as respective values of said control signal each associated with a different value of said wavelength;
• and
• an operative phase comprising the steps:
• using a digital signal corresponding to the required output wavelength to address said storage means and obtain an associated digital signal corresponding to an associated said control signal, and
• converting the thus-obtained associated digital signal into said analog control signal, for application to said control electrode.