An electro-optical modulator device and method are provided. The device comprises a light modulator unit having a first Cathode for exposing to input light; and an electric field source configured to create an electric field affecting a change in the refractive index of the first Cathode, thereby effecting a change in the propagation of light reflected from or transmitted through the first Cathode, said light from the first Cathode enabling to affect the operation of an external light sensitive electronic device.