Patent ID: 8742861

Claim:
A surface acoustic wave resonator comprising: a piezoelectric substrate; and an interdigitated transducer including electrode fingers for exciting surface acoustic waves disposed on the piezoelectric substrate, wherein a line occupying ratio is defined as a value obtained by dividing a width of one of the electrode fingers by a distance between a center line of a gap between the one electrode finger and an adjacent one of the electrode fingers to one side thereof and a center line of a gap between the one electrode finger and the adjacent one of the electrode fingers to the other side thereof, wherein the interdigitated transducer includes a region formed by sequentially changing the line occupying ratio from a center to both edges thereof so that the frequency gradually becomes lower from the center to both edges than the frequency at the center of the interdigitated transducer, and wherein the piezoelectric substrate is a crystal substrate with an Euler angle (−1° to +1°, 113° to 135°, ±5°).