Chen Wen, Chen Xudong, Sheppard Colin J R
Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576, Singapore.
Appl Opt. 2011 Oct 10;50(29):5750-7. doi: 10.1364/AO.50.005750.
In this paper, we propose a method using structured-illumination-based diffractive imaging with a laterally-translated phase grating for optical double-image cryptography. An optical cryptosystem is designed, and multiple random phase-only masks are placed in the optical path. When a phase grating is laterally translated just before the plaintexts, several diffraction intensity patterns (i.e., ciphertexts) can be correspondingly obtained. During image decryption, an iterative retrieval algorithm is developed to extract plaintexts from the ciphertexts. In addition, security and advantages of the proposed method are analyzed. Feasibility and effectiveness of the proposed method are demonstrated by numerical simulation results.
在本文中，我们提出了一种基于结构照明的衍射成像方法，该方法使用横向平移的相位光栅实现光学双图像加密。设计了一种光学密码系统，并在光路中放置多个仅含随机相位的掩模。当相位光栅在明文之前横向平移时，可以相应地获得几个衍射强度图案（即密文）。在图像解密过程中，开发了一种迭代检索算法从密文中提取明文。此外，还分析了所提方法的安全性和优点。数值模拟结果证明了所提方法的可行性和有效性。
