基于角谱插值的数字全息在任意斜面的重建方法

为了在任意非平行斜面上重建数字全息像,提出了一种基于角谱旋转变换和插值的数字处理方法,用角谱衍射理论进行了分析,给出了正反旋转两种数字插值方法,基于旋转变换信息量不变的原则分析了倾斜面上的抽样间隔取值范围,其大小取决于斜面带宽和全息图空间带宽积大小。实现了在71°倾斜物面上的全息重建,消除了倾斜造成的局部离焦现象,同时验证了算法在斜面上抽样间隔取值范围。

Reconstructing Method of Digital Holograms on Arbitrarily Tilted Planes Based on Angular Spectrum Interpolation

To reconstruct a image on arbitrary tilted plane from a digital hologram, a reconstruction method based on angular spectrum transform and interpolation processing method is proposed. The angular spectrum diffraction theory is applied to analyze the proposed method. Two interpolation algorithms of forward and inverse spectrum rotations are presented. The sampling interval is analyzed based on the condition of information conservation of rotation transform. It′s shown that the interval values depend on the bandwidth of the spectrum on tilted plane and the spatial-band width product of the hologram. The holographic reconstruction is realized on a 71° single axis rotation. The partially defocus blurred aberration resulted from the tilted object plane is removed by this method. Meanwhile the range of sampling interval on tilted plane is presented.