In this paper, a speckle noise suppression method in phase-only holographic display based on an improved Gerchberg–Saxton(GS) algorithm is proposed. The computer generated hologram(CGH) is calculated by employing triple-constraint Gerchberg–Saxton(TCGS) algorithm. The amplitude distribution and the phase distribution in the signal domain are simultaneously constrained as the desired distribution to suppress speckle noise, meanwhile, the phase distribution in the non-signal domain is also constrained to increase the uniformity of the reconstructed object. In addition, the setting of signal domain ratio has a great influence on the quality of the final reconstructed object. It is found that when the signal domain ratio accounts for 25%− 65%, the quality of the reconstruction is much better. Furthermore, by putting forward some restrictions on sample intervals, the multi-plane three-dimensional(3D) object calculated by TCGS algorithm will defocus without fragmentation and fracture phenomenon. Both simulation and experiment results show that the speckle contrast is lower than 0.05, which verifies the effectiveness of the algorithm.

本文提出了一种基于改进的Gerchberg-Saxton(GS)算法的单相全息显示中的散斑噪声抑制方法。计算机生成的全息图（CGH）是通过采用三重约束 Gerchberg-Saxton（TCGS）算法计算出来的。信号域中的幅度分布和相位分布同时被约束为期望分布以抑制散斑噪声，同时非信号域中的相位分​​布也被约束以增加重构对象的均匀性。此外，信域比的设置对最终重建对象的质量影响很大。发现当信域比占 25%−65% 时，重建的质量要好得多。此外，通过对采样间隔提出一些限制，TCGS算法计算出的多平面三维（3D）物体将散焦，不会出现碎裂和断裂现象。仿真和实验结果均表明散斑对比度小于0.05，验证了算法的有效性。