Patent ID: 8154780

Claim:
A holographic image projector comprising a holographic image projection system for projecting an image at an acute angle onto a surface, the system comprising: a spatial light modulator (SLM) to display a hologram; an illumination system to illuminate said displayed hologram; projection optics to project light from said illuminated displayed hologram onto said surface at an acute angle to form said image; and a processor having an input to receive input image data for display and an output to provide hologram data for said spatial light modulator, and wherein said processor is configured to: input image data; convert said input image data to target image data; generate from said target image data hologram data for display as a hologram on said spatial light modulator to reproduce a target image corresponding to said target image data; and output said hologram data for said spatial light modulator; wherein said target image is distorted to compensate for said projection of said hologram at said acute angle to form said image; wherein said holographic image projector is configured to stand on said surface and project downwards onto said surface, away from said projector, at said acute angle; and wherein diffracted light from a single pixel of said hologram displayed in said SLM contributes to a substantial entirety of said projected image, wherein said diffracted light is distorted, and wherein said conversion of said input image data to said target image data further comprises compensating for variations in per unit area brightness of said projected image due to said acute angle projection by applying a scale factor to a value of a pixel in said target image data, wherein said scale factor is dependent on a location in two dimensions of said pixel in a distorted target image space represented by said target image data.