Patent ID: 8385586

Claim:
A flat loudspeaker comprising a plurality of stacked flat speaker units each comprising: a perforated electrode structure having a plurality of holes; a vibrating membrane structure, each of the vibrating membrane structures comprises an electret vibrating membrane and a conductive electrode stacked together; and a supporting layer disposed between the vibrating membrane structure and the perforated electrode structure, the supporting layer having a plurality of supporting members, wherein the vibrating membrane structure, the supporting layer, and the perforated electrode structure are sequentially stacked to form the flat speaker unit, the stacked flat speaker units comprise at least two of the flat speaker units having the conductive electrodes respectively located at two utmost opposite sides of the flat loudspeaker and grounded, and each of the vibrating membrane structures has a corresponding perforated electrode structure located at the side of the flat speaker unit, such as the perforated electrode structures facing the corresponding vibrating membrane structures.