Illumination Method for Displaying Different Graphical Layouts

A method, comprising:

• receiving an optical beam, defined by a wave-vector k1 or by a wave-vector k2, by a substrate of optical material comprising a first surface and a second surface, wherein at least two areas on said substrate each comprising one of at least two types of diffractive elements disposed on the first or the second surface of the substrate, wherein periodic lines of a first of said at least two types of diffractive elements have a direction of said periodic lines substantially different from a direction of further periodic lines of a second of said at least two types of diffractive elements;
• propagating said optical beam substantially between said first and said second surfaces due to a total internal reflection;
• diffracting, if said optical beam is defined by said wave-vector k1, at least part of said optical beam defined by said wave-vector k1 in one of said at least two areas comprising said first of said at least two types of diffractive elements providing an output optical beam out of the first or the second surface, wherein said optical beam defined by said wave-vector k1 is diffracted or reflected in another of said at least two areas comprising the second of said at least two types of diffractive elements without providing said output optical beam out of the first or the second surface or
• diffracting, if said optical beam is defined by said wave-vectors k2, at least part of said optical beam defined by said wave-vector k2 in said another of said at least two areas comprising said second of said at least two types of diffractive elements providing a further output optical beam out of the first or the second surface, wherein said optical beam defined by said wave-vector k2 is diffracted or reflected in said one of said at least two areas comprising said first of said at least two types of diffractive elements without providing said further output optical beam out of the first or the second surface.

An electronic device, comprising:

• an optical device, comprising
• a substrate of optical material comprising a first surface and a second surface;
• and
• at least two types of diffractive elements each disposed on one of at least two areas on said substrate on the first or the second surface, wherein periodic lines of a first of said at least two types of diffractive elements have a direction substantially different from a direction of further periodic lines of a second of said at least two types of diffractive elements according to a predetermined criterion,
• wherein
• at least part of an optical beam defined by a wave-vector k1 and confined between said first and said second surfaces is diffracted in one of said at least two areas comprising said first of said at least two types of diffractive elements providing an output optical beam out of the first or the second surface, wherein said optical beam defined by said wave-vector k1 is diffracted or reflected in another of at least two areas comprising said second of said at least two types of diffractive elements without providing said output optical beam out of the first or the second surface, and
• at least part of another optical beam defined by a wave-vector k2 and confined between said first and said second surfaces is diffracted in said another of at least two areas comprising said second of said at least two types of diffractive elements providing a further output optical beam out of the first or the second surface, wherein said another optical beam defined by said wave-vector k2 is diffracted or reflected in said one of said at least two areas comprising said first of said at least two types of diffractive elements without providing said further output optical beam out of the first or the second surface,
• optical sources for providing at least two types of optical beams defined by wave-vectors k1 and k2;
• and
• a component comprising said substrate and said optical sources.