摘要 |
To provide a surface elastic wave apparatus that suppresses occurrence of fine ripples within a pass band, improves insertion loss and enhances the degree of balance. First and second surface acoustic wave elements (14, 15) that are parallel-connected to a surface acoustic wave resonator (16) respectively have three or more odd-numbered IDTs (2-4, 5-7), each having a plurality of electrode fingers placed along a propagation direction of a surface acoustic wave that is propagated over a piezoelectric substrate (1), and reflectors (8, 20, 21, 10), each having a plurality of electrode fingers that are placed on the two ends of the IDT row, and among all the electrode fingers respectively possessed by the IDTs and reflectors, the polarities of the electrode fingers placed adjacent to a different IDT or reflector are arranged symmetrically centered on the IDT located in the center.
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