Reducing Defocused-Information Crosstalk to Multi-View Holography by Using Multichannel Encryption of Random Phase Distribution

• Published in: Applied sciences Vol. 12; no. 3; p. 1413
• Main Authors: Chuang, Chih-Hao, Chen, Chien-Yu, Chang, Hsuan-Ting, Lin, Hoang-Yan, Kuo, Chuan-Feng
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.02.2022
• Subjects: Algorithms; computer-generated holography; Data encryption; Fourier transforms; Mean square errors; Noise; optical encryption algorithm; reducing defocused-information crosstalk; Three dimensional imaging; Wavelet transforms
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app12031413

A new optical encryption algorithm, called the random-phase encryption algorithm, is proposed in this study. When this algorithm was applied in constructing computer-generated holograms, the out-of-focus image crosstalk was effectively reduced, and the image quality was greatly enhanced. In this study, the researchers encrypted each multi-depth or multi-view random phase sub-image with the phase-locked key to generate multi-channel encryption phase information. During the reconstruction, the switch of the phase-locked key of the sub-image was found to achieve different image reconstruction effects with different views or depths. This algorithm proved to substantially reduce the out-of-focus image crosstalk and to enhance the reconstruction quality of the original computer holography without concerning the mutual interference among the information of each view for multi-view and multi-depth holograms.