| 摘要 |
An acoustic transducer (10) which can be made small in size, i.e., in width, length and thickness so as to fit into a credit card size package. The transducer (10) comprises a flat frame (12) having an opening (14) therethrough. A pair of diaphragms (16) of a piezoelectric plastic material extend across the opening (14) in the frame (12) along opposite sides of the frame. The diaphragms (16) are stretched in at least one direction and are bonded to the frame (12) under tension in the direction of the stretch. The diaphragms (16) are bonded together at a position within the opening in the frame. The diaphragms (16) are coated in both surfaces with conductive metal films (18, 20). The inner metal films (18) on the diaphragms which are opposed to each other are electrically connected together and the outer metal films (20) are electrically connected together. |
