  Soft surfaces impacted by liquid drops trap more air than their rigid
counterpart. Due to the extended lifetime of this air film, the dynamics and
eventual rupture of trapped air film depend on its interaction with the air
cavity developed in the liquid during impact. In this work, we investigate the
interaction between air cavity collapse and air film rupture for drops
impacting on soft, hydrophobic surfaces using high-speed laser interferometry.
We first reveal three different rupture dynamics of the trapped air film: the
rupture may initiate either at the center of the dimple, at the edge of the
dimple or at a random point in the dimple's outer rim. We found that the
transition between these rupture dynamics depends on both the impact velocity
and the surface elasticity. Further, in the most special case of air-film
rupture, the so-called dimple inversion, the rupture is directly caused by the
collapsing air cavity in the droplet bulk. We further observe that in such
cases, high-speed jets occur. We then provide a detailed characterization of
the collapsing dynamics of the air cavity and subsequent jetting.
