Electrically Adaptive and Shape-Changeable Invertible Microlens.

Existing soft actuators for adaptive microlenses suffer from high required input voltage, optical loss, liquid loss, and the need for assistant systems. In this study, we fabricate a polyvinyl chloride-based gel using a new synergistic plasticization method to achieve simultaneously a high optical transparency and an ultrasoft rubber-like elastic behavior with a large voltage-induced deformation under a weak electric field. By compressing the smooth gel between two sets of annular electrodes, a self-contained biconvex microlens is realized that is capable of considerable shape changes in the optical path. Each surface of the dual-curvature microlens can be independently adjusted to focus or scatter light to capture real or virtual images, yield variable focal lengths (+31.8 to -11.3 mm), and deform to various shapes to improve aberrations. In addition to simple fabrication, our microlens operates silently and consumes low power (0.52 mW), making it superior to existing microlenses.