The invention includes a method and apparatus for modulating one or both
of spectral phase and amplitude of a received optical signal. The
apparatus includes a spatial dispersion mechanism for spatially
dispersing the received optical signal to enable optical communication of
the received optical signal to an array of modulators. The apparatus
includes a modulating mechanism having a first modulating component and a
second modulating component. A first portion of the spatially dispersed
optical signal is incident on the first modulating component and a second
portion of the spatially dispersed optical signal is incident on the
second modulating portion. The apparatus further includes a controller
coupled to the modulating mechanism. The controller is adapted for moving
the first and second modulating components in a direction normal to their
planes for modulating one or both of phase and amplitude of the received
optical signal.