利用数字全息和相位恢复算法实现信息加密

Information Encryption Based on Digital Holography and Phase Retrieve Algorithm

提出了一种基于数字全息技术和相位恢复算法的信息加密方法。运用相位恢复算法得到数字全息图的纯相位频谱分布,实现了对全息图的加密;对纯相位频谱分布实施逆傅里叶变换(IFT)则可以得到解密后的全息图。利用菲涅耳近似法和卷积法对解密后的全息图进行数字重构得到了再现像。该加密方法区别于常用的随机相位加密方法,不再需要制作随机相位板。实验结果表明,该加密方法既适用于对二维图像加密,也适用于对三维物体进行加密。

An information encryption method is proposed based on digital holographic technique and phase retrieve algorithm. The phase-only information of a digital hologram is gotten by using phase retrieve algorithm, and then the hologram is encrypted. The reconstructed hologram can be obtained by applying inverse Fourier transform （IFT） to encrypt the hologram. The image can be reconstructed through Fresnel approximation method and convolution method. The presented method is quite different to ordinary random phase encryption methods, and the random phase element is not needed. Experimental results show that this method is suitable for two- and threedimensional object encryption.