Reconstruction of synthetic aperture digital Fresnel hologram by use of the screen division method

Synthetic aperture digital holography can effectively increase the recording area of digital hologram, which is propitious to extend the range and improve the resolution of the reconstruction image. However, the area of synthetic aperture digital hologram is usually very large, and thus if it is directly reconstructed, the numerical reconstruction process may can't progress in order for the limitation of the disposal capability of computer. Therefore, a screen-division reconstruction method for synthetic aperture digital Fresnel hologram is proposed in the paper. Relatively to the direct reconstruction method, the screen division reconstruction method can effectively reduce the area of the hologram participant in the numerical operation process and thus make it possible to reconstruct the synthetic aperture digital Fresnel hologram which area exceeds the disposal capability of computer. The synthetic aperture digital Fresnel hologram with large area is acquired by the precise control for the removal of CCD array and then reconstructed by the proposed screen division reconstruction method. The experimental results show that, the introduced numerical reconstruction method can well correct the position and phase distribution of the sub-reconstructed-images and obtain accurate synthetic numerical reconstruction image.