An electro-optical modulator includes a substrate, a first electrode over
the substrate, a second electrode over the first electrode, the first
electrode and second electrode being capable of providing an electric
field between the first electrode and the second electrode, and a
modulating structure between the first electrode and the second
electrode, the modulating structure containing at least one liquid
crystal cell capable of operating in one of a reflective mode and a
transmissive mode under the control of the electrical field.