Bubbles are present in many fields in softmatter physics. Sometimes, they are a nuisance, for example as cavitation bubbles at propellers that will drastically shorten the lifetime of the propeller material. But bubbles can also be used to assess information of flow parameters, measure the deposited energy or be an indicator for the density of a fluid.
That last point is of particular interest for us, and we started a project to measure the size of bubbles present in solids and fluids. Since the bubbles are in the range of 1 um in diameter, sizing them with optical means is not a trivial task. We image bubbles in different surroundings with various microscopy techniques and develop imaging models to be able to measure the diameter of the bubbles.