| 摘要 |
PURPOSE: A voice film of a multi layered structure for a flat speaker is provided to increase the number of winding a coil or the magnetic flux density of the coil, thereby increasing the strength of an induced electromotive force. CONSTITUTION: A voice film(40) of a multi layered structure is made of a PCB and a coil pattern. The beginning point of a coil pattern of the top PCB(PCB1) is connected to a first power line(42a). The end point of a coil pattern of the bottom PCB(PCBn-1) is connected to a second power line(42b). The PCB is made of an insulation material like a polyimide material. The coil patterns are formed on PCB boards of a middle layer. |
