Li Bingyi, Wang Jun, Chen Chun, Li Yuejia, Yang Ruoxue, Chen Ni
Opt Express. 2020 Oct 12;28(21):31373-31385. doi: 10.1364/OE.401679.
The spherical computer-generated hologram is inevitably suffered from the speckle noise since it is necessary to add random phase to the object to ensure the scattering characteristic of reconstructed image. The speckle noise seriously degrades the quality of reconstructed image especially for a spherical phase-only hologram (SPOH). In this paper, spherical self-diffraction iteration (SSDI) algorithm is proposed to suppress the speckle noise in the SPOH. The algorithm is based on spherical self-diffraction (SSD) model which is a special case of spherical back-propagation (SBP) model at limit condition. The correctness of SBP and SSD as well as the effectiveness of SSDI algorithm are verified by numerical simulations. Meaningfully, the proposed method significantly outperforms the conventional methods in speckle suppression performance and computing speed. As far as we known, models of SBP and SSD as well as conception of SSDI are firstly proposed and applied for speckle suppression of SPOH.
由于需要向物体添加随机相位以确保重建图像的散射特性，因此计算机生成的球面全息图不可避免地会受到散斑噪声的影响。散斑噪声严重降低了重建图像的质量，尤其是对于纯球面相位全息图（SPOH）而言。本文提出了球面自衍射迭代（SSDI）算法来抑制SPOH中的散斑噪声。该算法基于球面自衍射（SSD）模型，该模型是球面反向传播（SBP）模型在极限条件下的特殊情况。通过数值模拟验证了SBP和SSD的正确性以及SSDI算法的有效性。有意义的是，所提出的方法在散斑抑制性能和计算速度方面明显优于传统方法。据我们所知，SBP和SSD模型以及SSDI的概念是首次提出并应用于SPOH的散斑抑制。
