Reduction of coherent artifacts in dynamic holographic three-dimensional displays by diffraction-specific pseudorandom diffusion

An electroholographic display based on diffraction-specific computation can reduce speckle by electronic diffusion through selective addition of a pseudorandom sequence. Intensity fluctuation as a result of the introduction of pseudorandom noise does not affect three-dimensional (3-D) images significantly since spatial windows formed by diffused basis fringes do not widen noticeably at low pseudorandom spread, whereas the features of the fluctuation are much smaller than human visual resolution. Experimental results obtained on the Massachusetts Institute of Technology holographic video system confirmed that the diffusion smooths 3-D images and improves the intensity nonuniformity among horizontal holographic lines.