Self-generated off-axis holography in interferometric out-of-focus imaging of ice particles

ABSTRACT

Interferometric out-of-focus imaging of ice particles is realized. A review of the recent developments performed to analyse the speckle-like out-of-focus images of rough particles is first proposed. A remaining challenge is the analysis of overlapping out-of-focus images. In a second part, the overlapping defocused images of two nearby ice particles are analysed. If one particle is much smaller than the other one, the pattern constitutes an off-axis hologram whose analysis gives the exact size and shape of the biggest particle. Using two angles of view, we obtain a 3D description of the biggest ice particle.

KEYWORDS:

• Instrumentation
• metrology
• interferometric imaging
• digital holography

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors thank the French National Agency for financial support through the SIAMA project of program Investissements d’Avenir LabEx EMC3 Agence Nationale de la Recherche (ANR-10-LABX-09-01).