光学图 meaning in English

optical picture

Abstract : in this paper , a variety of encryption methods for optical image security are comparatively studied . according to the different method , the encrypted image can be transformed into white or color noise . the encryption phase can be the random phase or the chaotic sequence as well as the calculated result by used of the phase retrieval algorithm . the image quality and the correlative recognition ability of decrypted image are affected by the different part of the decryption phase and the amount of high frequency or low frequency used in the process of decryption
文摘:本文分析比较了多种实现光学图象相位加密的方法，发现不同方法获得的加密图象有不同类型的噪音分布.无论加密相位是随机相位模板、浑沌序列的相位列阵，还是用相位重构迭代算法计算的结果，它们都能起到加密图象的功能.解密图象的质量或被相关识别的能力与解密过程中所使用正确解密相位的不同部分以及高低频分量多少有关，且其依赖程度是由不同的加密方法自身决定