| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an acoustic wave resonator capable of increasing the steepness of pass characteristic in a high frequency side transition frequency band of an acoustic wave filter.SOLUTION: An acoustic wave resonator 1 includes: a piezoelectric substrate 2; and a first dielectric film 5 formed so as to cover an IDT electrode 3 that excites a major elastic wave on the piezoelectric substrate, first and second reflector electrodes 4a and 4b which are disposed at both sides of the IDT electrode along a propagation direction of the major elastic wave, the IDT electrode, and the first and second reflector electrodes. The acoustic wave resonator is configured so that at least maximum frequency of a cutoff frequency band at one reflector electrode of the first and second reflector electrodes is lower than an antiresonance frequency of the major elastic wave.</p> |
