Adaptive contrast enhancement and effect of non-linear exponential merit function on computer-generated holograms

Abstract

A merit function that integrates energy redistribution into the Gerchberg–Saxton method for computer-generated holograms is introduced for enhancing the contrast and increasing the dynamic range of reconstructed holographic images. It employs a non-linear exponent to adjust intensity weighting and a dynamic range shift to selectively suppress noise in visually sensitive regions. The proposed non-linear merit function can bring about superior contrast ratios and maintain overall luminance, producing sharper and more vivid reconstructed holographic images. The optical reconstruction results indicate a 6.25% improvement in peak signal-to-noise ratio and a 67.85% improvement in dynamic range index.