数字全息系统是一种非常先进的成像系统,但相干光源数字全息系统中散斑噪声会对全息图的质量产生不利影响,常规实验降噪或基于传统神经网络算法降噪方法均存在不足。为实现全息图中的散斑降噪以及权衡降噪效率问题,提出一种基于卷积神经网络的单幅全息图快速降噪算法,使用散斑噪声数据集对多等级神经网络进行训练。理论分析及实验结果表明卷积神经网络应用于数字全息图的频谱域去噪能有效提高全息图的质量,且仅使用一幅全息图就可以有效地处理不同等级散斑噪声,在保持去噪性能的前提下,能最大限度保存全息图有效干涉条纹。

Digital holographic system is a promising image-forming system, but speckle noise in the coherent light source of digital holographic system adversely affects the quality of holograms. There are some disadvantages in conventional experimental noise reduction or traditional neural network-based noise reduction methods. In order to realize speckle noise reduction in holograms and balance the efficiency of noise reduction, a fast noise reduction algorithm based on convolutional neural network for single hologram is proposed, and the speckle noise dataset is used to train multilevel neural networks. Theoretical analysis and experimental results show that the convolution neural network applied in digital hologram spectrum domain denoising can effectively improve the quality of the hologram, and multilevel speckle noise can be effectively processed by only one hologram. which can save the effective interference fringes of holograms to the maximum extent while maintaining the denoising performance.