US Patent 7470028 Image projection device and method

A device for forming an image on a screen is described that comprises a coherent illumination means, an electrically addressed spatial light modulator means located in the path of light from the coherent illumination means, means for producing computer generated hologram images for display on the electrically addressed spatial light modulator means, and optics to direct light diffracted by the electrically addressed spatial light modulator means to the screen. The device is arranged so that a computer generated image or images displayed by the electrically addressed spatial light modulator means result in a two dimensional image being formed at the screen.