Micro parts & particles self assembly are of great interest in research as a bottom-up approach, especially when it combines with microfluidic application. In this particular example, we image the deformation of air-water interface by small circular raft with designed edge profiles at 1000 frames per second to study the dynamics of raft rotation and assembly.
Two 100 micron diameter rafts are floating on the surface of a liquid. The shape of the raft influences the deformation of the liquid surface and therefore the dynamical behavior of both rafts and their coupling. It is nicely illustrated by the movie with raw phase images, where lines represent isolevel contours spaced by 330 nanometers in height (better to see below in the static pictures).
Dynamic and programmable self-assembly of micro-rafts at the air-water interface, Science Advances 24 May 2017: Vol. 3, no. 5, e1602522
DOI: 10.1126/sciadv.1602522