Dynamic spectral equalizer using free-space dispersive optics combined with a polymer-dispersed liquid-crystal spatial light attenuator

We describe the principle of a dynamic spectral equalizer (DSE), combining high dispersive capabilities of free-space wavelength-demultiplexing optics with a polarization independent polymer-dispersed liquid-crystal spatial light modulator (SLM), to provide wide-spectral-range quasi-continuous variable-gain attenuation and flattening. Preliminary results on C band are presented and discussed, as well as possible extensions toward C + L bands and metropolitan network functionalities.