在电子商务、军事侦察等应用中，往往需要实现对多图像的信息加密，它已成为信息安全领域的研究热点。随着获取信息量的增大，迫切需要新的、安全高效的加密方法替代传统的计算机加密算法。光学加密方法具有多维度、并行性等诸多优点，是现代密码技术发展的一个重要方向。但许多现有光学加密方案存在着系统结构较复杂、工作条件较苛刻、器件成本较高等问题，制约着光学加密技术在实际中的进一步应用。 本项目提出一种新型光电混合型多图像加密系统，它以光学扫描全息技术为基础，结合相位编码的光学加密原理，在双瞳光学系统中实现对较大空间范围内、沿纵向位置排列的多幅图像进行加密，并将加密结果直接存贮在计算机中；通过合理设计解码函数，减少数字图像重建时的串扰影响，提高加密容量；建立原理性实验装置，在级联和并联工作模式下，验证各项理论分析及数值模拟结果，为今后多图像光学加密技术的实用性研究提供理论和技术积累。

Multiple image encryption has found uses usually in areas such as electronic commerce and military reconnaissance, and it has become a research hotspot in the field of information security. With the increase of information, new alternatives with high safety and efficiency are urgently needed to replace the traditional algorithms as the encryption method for images. To the development of modern cryptography , encryption method based on optical means is an important direction because it has advantages of multidimension and parallelism. However, more complex system structures, relatively harsh working conditions and higher cost of devices are the main problems of the existing optical encryption schemes, which block the further applications of optical encryption technique in practice. This project proposes a new type of photoelectric hybrid image encryption system, which based on the optical scanning holography as well as the principle of phase encoding. Multiple images, arranged in a relatively large space and along in the longitudinal position, can be encrypted in a two-pupil optical system, and the encoding results can be stored in a computer directly. Cross-talks in the reconstruction of digital image may be reduced and encryption capacity may be improved by reasonable design of decoding function.The facility of principle experiment will be established, and the theoretical analysis and numerical simulation results will be verified under the condition of cascade and parallel mode. The results of this project may be a theoretical and technical background in the future for the practicability research of the optical technique used for multiple image encryption.