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Updated: May 15, 2026
10:16
Digital Inline Holographic Microscopy (DIHM) of Weakly-scattering Subjects
Published on: February 8, 2014
Analysis and adaptation of convolution algorithms to reconstruct extended objects in digital holography.
Pascal Picart1, Patrice Tankam
1LUNAM Université, Université du Maine, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 6613, Laboratoire d’Acoustique de l’Université du Maine (LAUM), Avenue Olivier Messiaen, 72085 LE MANS CEDEX 9, France. pascal.picart@univ‐lemans.fr
Applied Optics
|January 8, 2013
Summary
This study presents convolution algorithms for reconstructing off-axis digital holograms by analyzing spatial spectral properties. Three methods, including zero padding and spectrum scanning, are explored for spatial bandwidth extension and objectively compared through experiments.
Area of Science:
- Optics and Photonics
- Digital Holography
- Image Reconstruction
Background:
- Reconstructing off-axis digital holograms presents challenges due to convolution.
- Understanding the spatial spectral properties of holograms is crucial for accurate reconstruction.
- The localization property of the Fourier spectrum requires specific handling.
Purpose of the Study:
- To develop and compare convolution algorithms for off-axis digital hologram reconstruction.
- To investigate methods for addressing spatial bandwidth limitations in hologram reconstruction.
- To provide experimental validation for theoretical approaches.
Main Methods:
- Analysis of spatial spectral properties of digital holograms.
- Derivation of sampling requirements for transfer functions.
- Implementation and comparison of three spatial bandwidth extension techniques: zero padding, spectrum scanning, and adjustable magnification.
Main Results:
- Successful reconstruction of off-axis digital holograms using developed convolution algorithms.
- Demonstration of spatial bandwidth extension techniques to improve reconstruction fidelity.
- Objective comparison of the performance of different algorithms through experimental results.
Conclusions:
- The proposed convolution algorithms effectively reconstruct off-axis digital holograms.
- Spatial bandwidth extension methods offer viable solutions for hologram reconstruction challenges.
- Experimental validation confirms the efficacy and comparative performance of the presented algorithms.
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