Patent ID: 6924920

Claim:
Apparatus for light beam modulation, said apparatus comprising: a source of a beam of accelerated electrons up to velocity v; a light source with wavelength λ providing an optical beam to be modulated; a dielectric wave-guiding structure with refractive index n having at least two surfaces: (c) an irradiated surface for optical beam input; and (d) a transforming surface for optical field transformation into a delayed electromagnetic wave and for converting, wherein the angle between said surfaces is equal to α and n*sin(α)=(c/v)>1, whereby a beam of electrons is directed along a path extending over said transforming surface so that said beam interacts with said dielectric structure to produce interaction electromagnetic radiation as a fundamental mode of said radiation having the same phase-frequency characteristics as said delayed electromagnetic wave; and whereby the direction of the beam of electrons is manipulated to change the height of said beam over the transforming surface and to regulate energy exchange between moving electrons and said delayed electromagnetic wave so that predictable modulation is achieved for an optical field passed through said dielectric wave-guiding structure.