Phase Distribution Matters: On the Importance of Phase Distribution Alignment (PDA) in Holographic Applications

摘要

Phase distribution plays a critical role in various holographic applications; it affects the randomness within phase holograms, which, in turn, influences the viewing angle, speckle noise, and compression efficiency of the hologram. It also impacts the accuracy of measuring distortion between two phase holograms. Unlike ordinary image signals, uniquely determining the probability distribution of a phase hologram can be challenging due to the inherent periodicity of phase values. Although this ambiguity could impair the performance of many holographic applications, it has received little attention in prior works. In this paper, we introduce the Phase Distribution Alignment (PDA) method, which can transform a phase hologram so that its phase distribution is centered at a predefined reference point, resolving the ambiguity without affecting the numerical reconstruction result. Furthermore, when provided with a source and target phase hologram, PDA can align the source to maximize the overlap with the target distribution. We demonstrate the practical benefits of PDA in a range of holographic applications, including neural phase hologram generation, compression, and phase-domain distortion measurement.