基于相息图迭代的随机相位加密

提出了一种将随机相位加密和相位恢复算法中的求解附加相位分布分二步实施的加密方法. 由于该方法的实质是通过在随机谱和相息图之间进行相位恢复迭代以确定相息图和密钥的相 位分布，因而能够减小图像的解密误差.在相息图相位离散化的迭代过程中，采用增大设计 冗余度的方法，降低了由相位离散化所带来的解密误差.最后，通过计算机模拟实验验证了 该方法在减小图像解密误差方面的有效性. 关键词： 随机相位 光学图像加密 相息图 二元光学 离散化误差 相位恢复算法

Kinoform-based iterative random phase encryption

We propose a kinoform-based iterative random phase encryption method, in which t he phase retrieval algorithm is divided into two steps: 1) random phase encrypti on and 2) iteration solving for phase distributions of both the key phase plate and the kinoform. Since the iterations are executed between a Fourier spectrum a nd the kinoform, the decryption errors can be effectively depressed. By the quan tization process for the phase distributions during the iterations, a method of increasing the abundance of design is used to depress the decryption errors. The simulation results are presented at the end, which agree well with the theoreti cal analysis.