Patent ID: 8169682

Claim:
Light modulator for representing complex-valued information, comprising an encoding surface and a certain structured retardation layer, where the encoding surface comprises an arrangement of pixels, whose transmissive or reflective phase shift can be controlled, where for encoding individual components of a complex number at least one given pixel of a pixel group of adjacent pixels of the encoding surface is assigned with the certain structured retardation layer, which causes an angle-specific change in an optical path length of an incident bundle of rays having linear polarisation, the angle-specific change relating to an angle between an exiting bundle of rays and the encoding surface, wherein the layer thickness of the retardation layer is dimensioned such that when encoding the individual components of a complex number the change in the optical path length through the retardation layer counteracts the angle-specific change in the retardation among individual pixels of the pixel group, and compensates the angle-specific change in the retardation at least partly or even entirely.