The present disclosure provides an optical equalizer for photonics system in an electric-optical communication network. The optical equalizer includes an input port and an output port. Additionally, the optical equalizer includes a filter having a number of stages coupled to each other in a multi-stage series with an output terminal of any stage being coupled to an input terminal of an adjacent next stage while the input terminal of a first stage of the multi-stage series being coupled from the input port. Each stage includes a tap terminal configured to pass an optical power factored by a coefficient of multiplication from the corresponding input terminal of the stage to a tap-output path characterized by a corresponding phase delay. Furthermore, the optical equalizer includes a combiner configured to sum up the optical powers respectively from the number of tap-output paths of the multi-stage series to the output port.