Electrically tunable optofluidic light switch for reconfigurable solar lighting.

We describe a reconfigurable lighting system for indoor solar illumination which provides a new way for solar energy conservation. We have experimentally demonstrated an electrically tunable optofluidic light switch which takes the key role for the reconfigurability. The working principle of the switch is based on applying a dielectrophoretic force on a thin oil film hence inducing a surface deformation and consequent leakage of the guided light propagating along the waveguide. A maximum modulation frequency of 2 Hz was achieved. The switch has the advantages of simple fabrication, compact size and low power consumption. The potential applications of such an optofluidic switch are also discussed.