| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve the thickness reduction in a piezoelectric type electroacoustic conversion device which serves as a receiver and a speaker. <P>SOLUTION: An outer peripheral part on an upper surface of a circular piezoelectric film 2 is bonded to a lower surface of a ring shaped frame 1 through an adhesive 3. A circular piezoelectric ceramic layer 6 is provided on the piezoelectric film 2. When a piezoelectric type electroacoustic conversion device is used as a receiver, only the piezoelectric film 2 is driven. When the piezoelectric type electroacoustic conversion device is used as a speaker, the piezoelectric film 2 and the piezoelectric ceramic layer 6 are simultaneously driven. In this case, since only the piezoelectric ceramic layer 6 is provided on the piezoelectric film 2, the thickness reduction is achieved. <P>COPYRIGHT: (C)2013,JPO&INPIT |
