Concept of a Focus-Tunable ECF Microlens and Fabrication of a Large Model Prototype

This paper proposes a novel elastomer-based tunable liquid-filled microlens by using an Electro-Conjugate Fluid (ECF) jet and MEMS technology. The common approach for tuning an elastomer-based microlens is to change the geometry of the boundary determined by the control pressure of the chamber by using an external pump. However, this paper proposes placing the ECF micropump inside the tunable microlens. The ECF is a dielectric fluid that works as a smart fluid, generating a powerful jet flow (ECF jet) when subjected to a high DC voltage. Since the ECF jet is generated only with a pair of tiny electrodes, the pumping mechanism can be easily inside the device. We fabricated the large model prototype of an ECF focus-tunable microlens by partially utilizing MEMS technology. The experimental results showed us the feasibility of the ECF microlens.