Evaluation of holographic reconstructed image quality considering non-uniform phase distribution in liquid crystal spatial light modulators

We quantitatively investigated the effect of two non-uniform phase distributions in parallel-aligned liquid crystal on silicon spatial light modulators on the image quality of a holographic image through numerical simulation. We conclude that, in the presence of a locally non-uniform phase distribution due to non-uniform liquid crystal (LC) alignment within a pixel, the diffraction efficiency of the first-order diffracted light decreases, and the brightness and uniformity of intensity of the image degrade. This is because the phase distribution near the boundary with the adjacent pixel changes from a rectangular to a sinusoidal wave shape. When there is a globally non-uniform phase distribution due to uneven thickness of the LC layer across the entire panel, the resolution characteristics and noise are affected. This is because the first-order diffracted light deviating from the original emission angle is present and the condensing point of the first-order diffracted light expands.