Patent ID: 7589439

Claim:
Electromechanical transducer element for converting mechanical force changes into electrical signals, the transducer having a layered structure and comprising: a signal layer and at least one ground layer ( 103 - 105 , 107 ) and dielectric layers comprising at least one charged elastic cellular electret film layer; a plurality of embossing structures essentially smaller than the signal and ground electrode layers in order to improve the electric properties, the embossing structures being separate structures from the signal and ground layers; the plurality of embossing structures sandwiching the at least one charged elastic cellular electret film layer and at least one electrode layer at certain areas essentially smaller than the signal and ground electrode layers, the plurality of embossing structures arranged under pressure in order to compress the at least one charged elastic cellular electret film layer most at the plurality of embossing structures and less elsewhere, and wherein the plurality of embossing structures comprises a dielectric or electrically conducting material.