| 摘要 |
PROBLEM TO BE SOLVED: To provide a balanced elastic surface wave device of high quality, which operates as a balanced type and is excellent in filter characteristic. SOLUTION: In the elastic surface wave device, a resonator electrode pattern is formed by providing a plurality of odd-numbered IDT electrodes in propagation direction of the elastic surface wave, and is provided in a plurality of stages on a piezoelectric substrate. One of the resonator electrode patterns formed in stages at both ends of the resonator electrode patterns is made a balanced or unbalanced input, and the other is made an unbalanced or balanced output. A resonator electrode pattern wherein an unbalanced input or an unbalanced output is formed is formed so that IDT electrodes arranged at both sides of a center IDT electrode become the same phase mutually, and a resonator electrode pattern wherein a balanced input or a balanced output is formed is formed so that IDT electrodes arranged at both sides of a center IDT electrode become reverse phase mutually.
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