Interferometric out-of-focus imaging of freezing droplets

Marc Brunel (1) , Mohamed Talbi (1) , Sébastien Coëtmellec (1) , Gérard Gréhan (1) , Yingchun Wu (2) , Justin Jacquot-Kielar (3)

1 CORIA - Complexe de recherche interprofessionnel en aérothermochimie
2 State Key Laboratory of Clean Energy Utilization
3 Department of Atmospheric and Oceanic Sciences [Montréal]

Interferometric out-of-focus images of freezing droplets are presented, and compared to simultaneous in-focus images. In these experiments, the freezing process is characterized by a breaking of the initial droplet’s glare points into a wide number of neighbor bright spots. The 2D-Fourier transforms of the interferometric patterns show an elliptical contour, with a central spot and eventually symmetric spread spots more or less intense, located around the position of the initial glare points of the liquid droplet (depending on the degree of freezing).

Keywords: Speckle 2D-autocorrelation; Freezing; Supercooled droplets; Interferometric out-of-focus imaging

Domains: Engineering Sciences [physics]; Optics / Photonic

Marc Brunel, Mohamed Talbi, Sébastien Coëtmellec, Gérard Gréhan, Yingchun Wu, et al.. Interferometric out-of-focus imaging of freezing droplets. Optics Communications, 2019, 433, pp.173-182. ⟨10.1016/j.optcom.2018.09.075⟩. ⟨hal-02110922⟩