Imaging quality analysis of phase-only holograms generated by point-based method with different edge-enhancement methods

Phase-only hologram is the way to generate holograms generated by computers. Although the imaging quality is generally acceptable, the edge and line patterns of the reconstructed images are fuzzy. In this paper, we propose two methods which are the image preprocessing of the original images based on edge-preserve to improve the imaging quality. One is to use the Smallest Univalue Segment Assimilating Nucleus (SUSAN) for the extraction of original image edge, and the other one is to employee the Gaussian filter in frequency domain to separate high frequency and low frequency. Numerical reconstructions and optical reconstructions with a phase-only spatial light modulator (SLM) show that these methods can enhance the edge and line patterns of the reconstructed images, and the merits and drawbacks of the imaging quality using two methods are analyzed.