| 摘要 |
<p>A filter device of the present invention is, for example, a duplexer (1). The duplexer (1) is provided with the following: a piezoelectric substrate (2); an IDT (3) formed on the main surface of the piezoelectric substrate so as to configure an elastic surface wave resonator; a wired electrode (5) electrically connected to the IDT (3); and acoustic members (different acoustic parts) (6) formed on the main surface of the piezoelectric substrate (2) near the IDT (3) and having acoustic impedance that is different from that of the piezoelectric substrate (2). The wired electrode (5) disposed near the IDT (3) is formed in an acoustic member (6).</p> |
