39.2: Fast layer‐based algorithm in computer‐generated holography by using the frequency sparsity of hologram

• Published in: SID International Symposium Digest of technical papers Vol. 52; no. S2; pp. 492 - 494
• Main Author: Jia, Jia
• Format: Journal Article
• Language: English
• Published: Campbell Wiley Subscription Services, Inc 01.08.2021
• Subjects: Algorithms; Computer-generated holography; Computing time; Fast algorithm; Fast Fourier transformations; Fourier transforms; Holograms; Holographic 3D display; Mathematical analysis; Occlusion; Pixels
• ISSN: 0097-966X; 2168-0159
• DOI: 10.1002/sdtp.15173

Fast layer‐based is proposed to speed up the calculation of computer‐generated holograms. In a layer‐based method, each layer image may contain large areas in which the pixel values are zero considering the occlusion effect among the different depth layers. By taking advantage of this feature, the fast algorithm only calculates the non‐zero image areas of each layer. In addition, two one‐dimensional fast Fourier transforms (1DFFT) are implemented to compute a 2DFFT without calculating the rows or columns in which the image pixels are all zero. Since the size of the active calculation is reduced, the computational speed is considerably improved. Numerical simulations and optical experiments are performed to confirm these methods. The results show that the total computational time can be reduced by 5 times for a three‐dimensional (3D) object of a train with 50 depth layers.