Localisation de microparticules dans un volume par holographie digitale hors axe et réduction d’ouverture

Abstract

Nowadays, digital holography is established as a three-dimensional visualization and measurement technique in different fields. Particularly in the field of fluid mechanics where it is widely used with its both configurations, on-axis and off-axis. The first one is characterized by two major drawbacks, the presence of different orders on the same axis and the limitation to low particle concentrations. The off-axis scheme overcomes these drawbacks by the spatial separation of the object and reference waves and the reconstructed orders on one hand and on the other hand could be adapted to high concentrations. However, in the reconstruction, the fact that the focusing depth is relatively high disrupts the exact location of the particles in the study volume. This thesis work consists to find a solution to this problem, which will be based on geometric optics, named the aperture reduction of the optical system.