US Patent 7738151 Holographic projector

A projection device having a coherent light beam-generator that generates a light beam and a beam expander disposed to receive the light beam and to emit an expanded light beam. The projection device also includes a digital micro-mirror device disposed to receive a holographic transform of an original image and to display the holographic transform for illumination by the expanded light beam into a holographic light beam with a convergent or focusing lens disposed to receive and modulate the holographic light beam and a liquid crystal plate volumetric image reconstructor that receives the focused holographic light beam and emits a 3-dimensional holographic image of the original image.