RESUMO
In off-axis digital holography, e.g., for detecting and imaging ultrafast phenomena, the interference region is confined to a limited region due to the short extent of the light pulse along the propagation axis. Therefore, the detected area of the object wavefront is limited. A recording method for enlarging the detected area in the above case is proposed in this Letter, in which multiple interferences between the object and the reference waves are obtained by spatial angular multiplexing. Experimental results demonstrate the validity of this method.
RESUMO
A novel numerical iterative approach is proposed to effectively eliminate the zero-order term and to improve the signal-to-noise ratio of the reconstructed image in off-axis digital holography. The iterations are conducted in the spatial domain, resulting in considerable reduction in the computational time and avoiding the subjectivity involved in selecting a filter window in spectral domain. These advantages promote the application of this approach in real-time detection processes. The feasibility of this approach is confirmed by mathematical deductions and numerical simulations, and the robustness of the proposed approach is tested by means of an experimentally obtained hologram.