Engineers at Rensselaer Polytechnic Institute (RPI) have developed capillarity-dominated technology where two adjoining ferrofluid droplets, called “liquid pistons”, saturated with metal nanoparticles oscillate and displace a surrounding liquid. Unlike their mechanical counterparts, these liquid pistons are highly tunable, scalable, and because they lack any solid moving parts, suffer no wear and tear.
For the RPI study, researchers demonstrated the use of the liquid pistons as a tiny camera lens. Passing light through the droplets, one can move the droplets back and forth, changing the focal length and bringing and object into and out of focus.
Moreover, as the droplets also displace the surrounding liquid, the liquid pistons could also act as micropumps and liquid switches for use in lab-on-chips or advanced drug delivery systems.
Article @ RPI: “Liquid Pistons” Could Drive New Advances in Camera Lenses and Drug Delivery…