Journal of Optics A Pure and Applied Optics

Securing information using digital optics

Xiaogang Wang, Yixiang Chen

Published Jan 3, 2007• 5 citations

Abstract

We present a new method to secure information based on digital optics in this paper. The input image to be encrypted is recorded as interferograms by use of two-step phase-shifting interferometry. Before transmitting through communication channels, the interferograms are encrypted as phase codes in fractional Fourier domain by using a computer generated random phase mask. The set of fractional orders and the computer generated random phase mask form the keys to the encrypted data. With the phase shifts generated in the recording process, the original image can be retrieved from the correct decrypted interferograms successfully. Computer simulations are presented to prove its validity.

DOI: 10.1088/1464-4258/9/2/005

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