An apparatus and method for use in an adaptive optical equalizer including, in one embodiment an optical equalizer having an input and output coupled to receive an incoming optical signal and configured to generate an output optical signal by phase modulation and/or amplitude modulation of the receive optical signal in response to electronic control signals. A photodiode is configured to receive the output optical signal and generate an representative current signal. A control signal generator is configured to generate the electronic control signals in accordance with predetermined criteria and in response to the representative current signal from the photodiode. An interferometer is connected to receive the incoming and output optical signal from the optical equalizer, the differential amplifier is configured to receive electronic versions of outputs from the interferometer for generating a difference signal and supplying the difference signal to the control signal generator.