Abstract: An electrostatic transducer in which a plurality of perforated sheets are arranged adjacent one another in a stack. A gas-filled gap separates each adjacent pair of sheets. Conductive surfaces on each sheet impose an electric field within the respective gaps. A flexible positioning mechanism disposed between each adjacent pair of sheets maintains a desired average thickness of the gaps. A high porosity gas reservoir structure is fixed to one outer end of the stack, such that gas may flow through the sheets between the respective gaps and the reservoir. A cover sheet fixed to an end of the stack opposite the reservoir prevents gas flow between the gaps and the region external to the stack during operation of the transducer within its intended operating frequency range.

Abstract: An electromechanical transducer having a substrate bearing a plurality of elastomeric microstructures with a microelectrode on each microstructure. A power supply is connected to the microelectrodes for controlled application to them of an electrical potential which alternately induces forces of attraction between adjacent pairs of microelectrodes, causing controlled, time-varying displacement of the microelectrodes. Alternatively, a further plurality of microelectrodes (or one or more macroelectrodes) are elastomerically supported above the microelectrodes, with the power supply being connected to the macroelectrode(s) such that the electrical potential applied between the microelectrodes and macroelectrode(s) alternately induces forces of attraction between the microelectrodes and macroelectrode(s), causing controlled, time-varying displacement of the microelectrodes relative to the macroelectrode(s). The macroelectrode(s) can also be applied to a side of the substrate opposite the microstructures.