为了消除光学扫描全息系统重建图像的离焦噪声，采用了随机相位编码和连通域标记方法。该方法利用了基于随机相位编码的光学扫描全息方法在聚焦层图像上的离焦噪声比传统的光学扫描全息方法更为分散的特点。只要选取合适的阈值，基于随机相位编码的光学扫描全息重建图像的离焦噪声就可以消除，而传统的光学扫描全息仍然存在较多的离焦噪声。实验结果表明该方法可以得到更好的重建图像效果。

In order to eliminate the defocus noise in reconstructed image of the optical scanning holographic system, the random phase coding and connected domain labeling methods are adopted. The advantage of this method is the defocus noise on in-focus image which will be more dispersive than traditional optical scanning holography if we use optical scanning holography based on random phase encoding. As long as the appropriate threshold is selected, the optical scanning holographic reconstruction based on random phase encoding is used. The defocus noise of the image can be eliminated, while the conventional optical scanning holography still has more defocus noise. The experimental results show that this method can achieve better reconstructed image effects.