Tunable liquid microlenses formed from dynamically re-configurable double emulsions

Abstract

Micro-scale optical components capable of on-demand reconfiguration of their internal morphology and composition would enable unprecedented control of light propogation on the microscale. Double emulsions formed from immiscible hydrocarbons and fluorocarbons offer a promising platform as reconfigurable micro-optical lenses. These droplet-based lenses can be reconfigured to strongly focusing, nearly transparent, or strongly scattering geometries. The dynamic variation of the lenses' optical interfaces can greatly enhance the lenses' ability to manipulate light. Finite Difference Time Domain and Raytracing techniques were used to characterize the optical properties of the drops and the simulations were verified experimentally immersing the lenses in an aqueous fluorescent medium in order to visualize their light manipulation capabilities. The lenses show a rapid response to external light stimuli or heat gradients and are susceptible to chemical triggers.