In this paper, the security of the cryptosystem with three phase-only masks (POMs) based on the interference has been evaluated. The security strength of the classical interference-based cryptosystem with two POMs has been enhanced by employing a random phase distribution to generate three POMs. This random phase distribution is utilized not only to replace the partial part of two POMs which could be used to retrieve information of the plaintexts directly, but also to modulate and generate an additional POMs; thus, the silhouette problem could be eradicated and key space would be enlarged. It is shown that the security strength of the interference-based cryptosystem has been improved; however, the random phase distribution is irrelative to the plaintexts and two POMs are dependent. Based on this finding, hybrid attacks including a known-plaintext attack (KPA) and phase-retrieval technique-based processes with different constraints have been proposed to crack the interference-based cryptosystem with three POMs and to release its silhouette problem. Numerical simulations have been carried out to validate the feasibility and effectiveness of the proposed attacks.

在本文中，已经评估了基于干扰的具有三个仅相位掩码（POM）的密码系统的安全性。通过采用随机相位分布来生成三个POM，增强了具有两个POM的经典基于干扰的密码系统的安全强度。这种随机相位分布不仅被用来代替两个POM的部分，而POM可以被用来直接获取明文的信息，而且还可以调制和生成一个额外的POM。因此，可以消除轮廓问题，并扩大关键空间。结果表明，基于干扰的密码系统的安全强度得到了提高。但是，随机相位分布与明文无关，并且有两个POM是相关的。基于此发现，提出了一种混合攻击，包括已知明文攻击（KPA）和具有不同约束条件的基于相位检索技术的过程，以破解具有三个POM的基于干扰的密码系统并释放其轮廓问题。已经进行了数值模拟，以验证所提出攻击的可行性和有效性。