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.