Off-axis compressed holographic microscopy in low-light conditions

Marcio M. Marim (1, 2) , Elsa Angelini (2) , Jean-Christophe Olivo-Marin (1) , Michael Atlan (3)

1 AIQ - Analyse d'Images Quantitative
2 Télécom ParisTech
3 IL - Institut Langevin - Ondes et Images (UMR7587)

This Letter reports a demonstration of off-axis compressed holography in low-light level imaging conditions. An acquisition protocol relying on a single exposure of a randomly undersampled diffraction map of the optical field, recorded in the high heterodyne gain regime, is proposed. The image acquisition scheme is based on compressed sensing, a theory establishing that near-exact recovery of an unknown sparse signal is possible from a small number of nonstructured measurements. Image reconstruction is further enhanced by introducing an off-axis spatial support constraint to the image estimation algorithm. We report accurate experimental recovering of holographic images of a resolution target in low-light conditions with a frame exposure of 5 μs, scaling down measurements to 9% of random pixels within the array detector.

Domaines: Optique [physics.optics]; Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Marcio M. Marim, Elsa Angelini, Jean-Christophe Olivo-Marin, Michael Atlan. Off-axis compressed holographic microscopy in low-light conditions. Optics Letters, 2011, 36 (1), pp.79. ⟨10.1364/OL.36.000079⟩. ⟨hal-00553203⟩