基于旋转照明光的数字全息相干噪声抑制

摘要

A method based on superposition of multiple reconstructed images is presented for coherent noise reduction of the phase image in digital holography.The proposed method obtains multiple off-axis holograms upon rotation of the illuminating light in the polar plane under a constant azimuthal angle.Both the tilt factor and lateral shift of the reconstructed phase distribution are compensated by using the phase compensation algorithm and digital image registration method respectively.The coherent noise in the synthesized images is significantly suppressed by averaging reconstructed imaging fields.The experimental results and the related statistical evaluation have demonstrated the effectiveness of this approach.%提出一种数字全息相干噪声抑制方法.首先在照明光方位角给定的前提下,通过在极向平面内连续旋转照明光,实现在多角度照明条件下记录离轴数字全息图.然后对所获得的全息图分别重构,同时利用倾斜相差补偿算法和数字图像自相关配准方法分别补偿再现像的相位倾斜及横向偏移.最后将重构像进行非相干叠加,从而有效抑制再现像的相干噪声.实验结果及相关统计评价数据皆验证了该方法的有效性.