A tunable liquid lens driven by a concentric annular electroactive actuator

We present a membrane sealed fluidic lens that is hydrostatically connected to a concentric ring-shaped electroactive elastomer. Electrical activation deforms the ring-shaped elastomer, which induces fluid passage between the lens part and the actuation part of the membrane. This changes the lens´s shape and therefore the focal length. The focal length ranges from 25.4 mm to 105.2 mm can be obtained with a voltage bias of 1.0 kV. Comparing to the existing fluidic lenses driven by electroactive polymers, this lens has a wider range of refractive power at a significantly lower actuation voltage. Our device finds applications in miniaturized optical components where adaptive focalization is paramount.