Displaying digital holograms on phase-only devices

Recently, there is an increasing trend of adopting digital holography in practical applications such as projectors, head-up display (HUD), and near-eye augmented reality (AR) devices. These demands have led to numerous research works in the past decade, focusing on developing low cost and compact holographic display system. Amongst these research works, investigation on generation of phase-only holograms has become an area of immense interest. A phase-only hologram (POH) has two major advantages. First, it can be displayed with a single phase-only SLM. Second, the reconstructed image is brighter, and free from the de-focused twin image. In this tutorial, a number of methods for the generation of POH, will be reviewed. Emphasis will be placed on methods that are non-iterative and computationally efficient, so that they can be applied to generate phase-only hologram at high frame-rate. Moreover, these works also have the advantage that the POHs generated can be displayed directly on the phase-only SLM with little or no optical accessories, hence simplifying the complexity and cost of the optical setup.