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Digital Holography Toolbox

Digital Holography presentation

Digital Holography (DH) is a 3-D imaging technique which has been widely developed during the past few decades thanks to the enormous advances in digital imaging and computer technology. This technique achieves 3-D reconstruction of objects from a 2D hologram-image and reaches accuracies in the range of - or smaller than - the wavelength. As 3-D information coded in a digital hologram can be recorded in one shot, this technique can be used with high speed cameras to perform time-resolved 3-D reconstructions of high speed phenomena. This metrological tool is used in experimental mechanics, biology, or fluid dynamics.

3D Reconstruction algorithms

Over the past decade, numerous algorithms for the analysis of holograms have been proposed. They are mostly based on a common approach to hologram processing: digital reconstruction based on the simulation of hologram diffraction. They suffer from artifacts intrinsic to holography: twin-image contamination of the reconstructed images, image distortions for objects located close to the hologram borders. The analysis of the reconstructed planes is therefore limited by these defects. In contrast to this approach, the inverse problems perspective does not transform the hologram but performs object detection and location by matching a model of the hologram. Information is thus extracted from the hologram in an optimal way, leading to two essential results: an improvement of the axial accuracy and the capability to extend the reconstructed field beyond the physical limit of the sensor size (out-of-field reconstruction).

We propose on this web page a Matlab toolbox dedicated to Inverse Problems approach for digital hologram reconstruction. Although this approach is a general approach, the proposed Toolbox is limited to 3D reconstruction of on line digital holograms of spherical micro-objects, typically droplets or bubbles.

Download

You can download the first released version of the toolbox using the links bellow. This toolbox is programmed to process the holograms of spherical particles. The next versions of the toolbox will contain more general approaches to target a wider range of applications.

Since the size of the files and folders are relatively big, we have divided them into four(4) .zip files. Please extract them all in the main folder of the toolbox //DHtoolbox v1.3/ .

Toolbox: File:DHtoolbox v1.3.zip

Graphical User Interface: File:GUI.zip

Simulated holograms: File:Simulations.zip and File:Raw holos.zip

Real holograms captured in [LMFA][1]: File:Holo LMFA.zip

Screenshot

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